correction + legend placement

crates/attestation/Cargo.toml

@@ -27,7 +27,6 @@ alloy-primitives = { version = "1.3.1", default-features = false }
 alloy-signer = { version = "1.0", default-features = false }
 alloy-signer-local = { version = "1.0", default-features = false }
 rand06-compat = { workspace = true }
-rangeset = { workspace = true }
 rstest = { workspace = true }
 tlsn-core = { workspace = true, features = ["fixtures"] }
 tlsn-data-fixtures = { workspace = true }

crates/attestation/src/builder.rs

@@ -5,7 +5,7 @@ use rand::{Rng, rng};
 use tlsn_core::{
     connection::{ConnectionInfo, ServerEphemKey},
     hash::HashAlgId,
-    transcript::TranscriptCommitment,
+    transcript::{TranscriptCommitment, encoding::EncoderSecret},
 };
 
 use crate::{
@@ -25,6 +25,7 @@ pub struct Sign {
     connection_info: Option<ConnectionInfo>,
     server_ephemeral_key: Option<ServerEphemKey>,
     cert_commitment: ServerCertCommitment,
+    encoder_secret: Option<EncoderSecret>,
     extensions: Vec<Extension>,
     transcript_commitments: Vec<TranscriptCommitment>,
 }
@@ -86,6 +87,7 @@ impl<'a> AttestationBuilder<'a, Accept> {
                 connection_info: None,
                 server_ephemeral_key: None,
                 cert_commitment,
+                encoder_secret: None,
                 transcript_commitments: Vec::new(),
                 extensions,
             },
@@ -106,6 +108,12 @@ impl AttestationBuilder<'_, Sign> {
         self
     }
 
+    /// Sets the secret for encoding commitments.
+    pub fn encoder_secret(&mut self, secret: EncoderSecret) -> &mut Self {
+        self.state.encoder_secret = Some(secret);
+        self
+    }
+
     /// Adds an extension to the attestation.
     pub fn extension(&mut self, extension: Extension) -> &mut Self {
         self.state.extensions.push(extension);
@@ -129,6 +137,7 @@ impl AttestationBuilder<'_, Sign> {
             connection_info,
             server_ephemeral_key,
             cert_commitment,
+            encoder_secret,
             extensions,
             transcript_commitments,
         } = self.state;
@@ -159,6 +168,7 @@ impl AttestationBuilder<'_, Sign> {
                 AttestationBuilderError::new(ErrorKind::Field, "handshake data was not set")
             })?),
             cert_commitment: field_id.next(cert_commitment),
+            encoder_secret: encoder_secret.map(|secret| field_id.next(secret)),
             extensions: extensions
                 .into_iter()
                 .map(|extension| field_id.next(extension))
@@ -243,7 +253,8 @@ mod test {
     use rstest::{fixture, rstest};
     use tlsn_core::{
         connection::{CertBinding, CertBindingV1_2},
-        fixtures::ConnectionFixture,
+        fixtures::{ConnectionFixture, encoding_provider},
+        hash::Blake3,
         transcript::Transcript,
     };
     use tlsn_data_fixtures::http::{request::GET_WITH_HEADER, response::OK_JSON};
@@ -274,7 +285,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { request, .. } = request_fixture(transcript, connection, Vec::new());
+        let RequestFixture { request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection,
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let attestation_config = AttestationConfig::builder()
             .supported_signature_algs([SignatureAlgId::SECP256R1])
@@ -293,7 +310,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { request, .. } = request_fixture(transcript, connection, Vec::new());
+        let RequestFixture { request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection,
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let attestation_config = AttestationConfig::builder()
             .supported_signature_algs([SignatureAlgId::SECP256K1])
@@ -313,7 +336,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { request, .. } = request_fixture(transcript, connection, Vec::new());
+        let RequestFixture { request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection,
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let attestation_builder = Attestation::builder(attestation_config)
             .accept_request(request)
@@ -334,8 +363,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { request, .. } =
-            request_fixture(transcript, connection.clone(), Vec::new());
+        let RequestFixture { request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection.clone(),
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let mut attestation_builder = Attestation::builder(attestation_config)
             .accept_request(request)
@@ -359,8 +393,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { request, .. } =
-            request_fixture(transcript, connection.clone(), Vec::new());
+        let RequestFixture { request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection.clone(),
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let mut attestation_builder = Attestation::builder(attestation_config)
             .accept_request(request)
@@ -393,7 +432,9 @@ mod test {
 
         let RequestFixture { request, .. } = request_fixture(
             transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
             connection.clone(),
+            Blake3::default(),
             vec![Extension {
                 id: b"foo".to_vec(),
                 value: b"bar".to_vec(),
@@ -420,7 +461,9 @@ mod test {
 
         let RequestFixture { request, .. } = request_fixture(
             transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
             connection.clone(),
+            Blake3::default(),
             vec![Extension {
                 id: b"foo".to_vec(),
                 value: b"bar".to_vec(),

crates/attestation/src/fixtures.rs

@@ -2,7 +2,11 @@
 use tlsn_core::{
     connection::{CertBinding, CertBindingV1_2},
     fixtures::ConnectionFixture,
-    transcript::{Transcript, TranscriptCommitConfigBuilder, TranscriptCommitment},
+    hash::HashAlgorithm,
+    transcript::{
+        Transcript, TranscriptCommitConfigBuilder, TranscriptCommitment,
+        encoding::{EncodingProvider, EncodingTree},
+    },
 };
 
 use crate::{
@@ -17,13 +21,16 @@ use crate::{
 /// A Request fixture used for testing.
 #[allow(missing_docs)]
 pub struct RequestFixture {
+    pub encoding_tree: EncodingTree,
     pub request: Request,
 }
 
 /// Returns a request fixture for testing.
 pub fn request_fixture(
     transcript: Transcript,
+    encodings_provider: impl EncodingProvider,
     connection: ConnectionFixture,
+    encoding_hasher: impl HashAlgorithm,
     extensions: Vec<Extension>,
 ) -> RequestFixture {
     let provider = CryptoProvider::default();
@@ -43,9 +50,15 @@ pub fn request_fixture(
         .unwrap();
     let transcripts_commitment_config = transcript_commitment_builder.build().unwrap();
 
-    let mut builder = RequestConfig::builder();
+    // Prover constructs encoding tree.
+    let encoding_tree = EncodingTree::new(
+        &encoding_hasher,
+        transcripts_commitment_config.iter_encoding(),
+        &encodings_provider,
+    )
+    .unwrap();
 
-    builder.transcript_commit(transcripts_commitment_config);
+    let mut builder = RequestConfig::builder();
 
     for extension in extensions {
         builder.extension(extension);
@@ -61,7 +74,10 @@ pub fn request_fixture(
 
     let (request, _) = request_builder.build(&provider).unwrap();
 
-    RequestFixture { request }
+    RequestFixture {
+        encoding_tree,
+        request,
+    }
 }
 
 /// Returns an attestation fixture for testing.

crates/attestation/src/lib.rs

@@ -79,6 +79,8 @@
 //!
 //! // Specify all the transcript commitments we want to make.
 //! builder
+//!     // Use BLAKE3 for encoding commitments.
+//!     .encoding_hash_alg(HashAlgId::BLAKE3)
 //!     // Commit to all sent data.
 //!     .commit_sent(&(0..sent_len))?
 //!     // Commit to the first 10 bytes of sent data.
@@ -127,7 +129,7 @@
 //!
 //! ```no_run
 //! # use tlsn_attestation::{Attestation, CryptoProvider, Secrets, presentation::Presentation};
-//! # use tlsn_core::transcript::Direction;
+//! # use tlsn_core::transcript::{TranscriptCommitmentKind, Direction};
 //! # fn main() -> Result<(), Box<dyn std::error::Error>> {
 //! # let attestation: Attestation = unimplemented!();
 //! # let secrets: Secrets = unimplemented!();
@@ -138,6 +140,8 @@
 //! let mut builder = secrets.transcript_proof_builder();
 //!
 //! builder
+//!     // Use transcript encoding commitments.
+//!     .commitment_kinds(&[TranscriptCommitmentKind::Encoding])
 //!     // Disclose the first 10 bytes of the sent data.
 //!     .reveal(&(0..10), Direction::Sent)?
 //!     // Disclose all of the received data.
@@ -215,7 +219,7 @@ use tlsn_core::{
     connection::{ConnectionInfo, ServerEphemKey},
     hash::{Hash, HashAlgorithm, TypedHash},
     merkle::MerkleTree,
-    transcript::TranscriptCommitment,
+    transcript::{TranscriptCommitment, encoding::EncoderSecret},
 };
 
 use crate::{
@@ -297,6 +301,8 @@ pub enum FieldKind {
     ServerEphemKey = 0x02,
     /// Server identity commitment.
     ServerIdentityCommitment = 0x03,
+    /// Encoding commitment.
+    EncodingCommitment = 0x04,
     /// Plaintext hash commitment.
     PlaintextHash = 0x05,
 }
@@ -321,6 +327,7 @@ pub struct Body {
     connection_info: Field<ConnectionInfo>,
     server_ephemeral_key: Field<ServerEphemKey>,
     cert_commitment: Field<ServerCertCommitment>,
+    encoder_secret: Option<Field<EncoderSecret>>,
     extensions: Vec<Field<Extension>>,
     transcript_commitments: Vec<Field<TranscriptCommitment>>,
 }
@@ -366,6 +373,7 @@ impl Body {
             connection_info: conn_info,
             server_ephemeral_key,
             cert_commitment,
+            encoder_secret,
             extensions,
             transcript_commitments,
         } = self;
@@ -383,6 +391,13 @@ impl Body {
             ),
         ];
 
+        if let Some(encoder_secret) = encoder_secret {
+            fields.push((
+                encoder_secret.id,
+                hasher.hash_separated(&encoder_secret.data),
+            ));
+        }
+
         for field in extensions.iter() {
             fields.push((field.id, hasher.hash_separated(&field.data)));
         }

crates/attestation/src/presentation.rs

@@ -91,6 +91,11 @@ impl Presentation {
                 transcript.verify_with_provider(
                     &provider.hash,
                     &attestation.body.connection_info().transcript_length,
+                    attestation
+                        .body
+                        .encoder_secret
+                        .as_ref()
+                        .map(|field| &field.data),
                     attestation.body.transcript_commitments(),
                 )
             })

crates/attestation/src/request.rs

@@ -144,7 +144,9 @@ impl std::fmt::Display for ErrorKind {
 #[cfg(test)]
 mod test {
     use tlsn_core::{
-        connection::TranscriptLength, fixtures::ConnectionFixture, hash::HashAlgId,
+        connection::TranscriptLength,
+        fixtures::{ConnectionFixture, encoding_provider},
+        hash::{Blake3, HashAlgId},
         transcript::Transcript,
     };
     use tlsn_data_fixtures::http::{request::GET_WITH_HEADER, response::OK_JSON};
@@ -162,8 +164,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { request, .. } =
-            request_fixture(transcript, connection.clone(), Vec::new());
+        let RequestFixture { request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection.clone(),
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let attestation =
             attestation_fixture(request.clone(), connection, SignatureAlgId::SECP256K1, &[]);
@@ -178,8 +185,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { mut request, .. } =
-            request_fixture(transcript, connection.clone(), Vec::new());
+        let RequestFixture { mut request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection.clone(),
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let attestation =
             attestation_fixture(request.clone(), connection, SignatureAlgId::SECP256K1, &[]);
@@ -197,8 +209,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { mut request, .. } =
-            request_fixture(transcript, connection.clone(), Vec::new());
+        let RequestFixture { mut request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection.clone(),
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let attestation =
             attestation_fixture(request.clone(), connection, SignatureAlgId::SECP256K1, &[]);
@@ -216,8 +233,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { mut request, .. } =
-            request_fixture(transcript, connection.clone(), Vec::new());
+        let RequestFixture { mut request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection.clone(),
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let attestation =
             attestation_fixture(request.clone(), connection, SignatureAlgId::SECP256K1, &[]);
@@ -243,8 +265,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { request, .. } =
-            request_fixture(transcript, connection.clone(), Vec::new());
+        let RequestFixture { request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection.clone(),
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let mut attestation =
             attestation_fixture(request.clone(), connection, SignatureAlgId::SECP256K1, &[]);
@@ -262,8 +289,13 @@ mod test {
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
         let connection = ConnectionFixture::tlsnotary(transcript.length());
 
-        let RequestFixture { request, .. } =
-            request_fixture(transcript, connection.clone(), Vec::new());
+        let RequestFixture { request, .. } = request_fixture(
+            transcript,
+            encoding_provider(GET_WITH_HEADER, OK_JSON),
+            connection.clone(),
+            Blake3::default(),
+            Vec::new(),
+        );
 
         let attestation =
             attestation_fixture(request.clone(), connection, SignatureAlgId::SECP256K1, &[]);

crates/attestation/src/serialize.rs

@@ -49,4 +49,6 @@ impl_domain_separator!(tlsn_core::connection::ConnectionInfo);
 impl_domain_separator!(tlsn_core::connection::CertBinding);
 impl_domain_separator!(tlsn_core::transcript::TranscriptCommitment);
 impl_domain_separator!(tlsn_core::transcript::TranscriptSecret);
+impl_domain_separator!(tlsn_core::transcript::encoding::EncoderSecret);
+impl_domain_separator!(tlsn_core::transcript::encoding::EncodingCommitment);
 impl_domain_separator!(tlsn_core::transcript::hash::PlaintextHash);

crates/attestation/tests/api.rs

@@ -1,5 +1,3 @@
-use rand::{Rng, SeedableRng, rngs::StdRng};
-use rangeset::set::RangeSet;
 use tlsn_attestation::{
     Attestation, AttestationConfig, CryptoProvider,
     presentation::PresentationOutput,
@@ -8,11 +6,12 @@ use tlsn_attestation::{
 };
 use tlsn_core::{
     connection::{CertBinding, CertBindingV1_2},
-    fixtures::ConnectionFixture,
-    hash::{Blake3, Blinder, HashAlgId},
+    fixtures::{self, ConnectionFixture, encoder_secret},
+    hash::Blake3,
     transcript::{
-        Direction, Transcript, TranscriptCommitment, TranscriptSecret,
-        hash::{PlaintextHash, PlaintextHashSecret, hash_plaintext},
+        Direction, Transcript, TranscriptCommitConfigBuilder, TranscriptCommitment,
+        TranscriptSecret,
+        encoding::{EncodingCommitment, EncodingTree},
     },
 };
 use tlsn_data_fixtures::http::{request::GET_WITH_HEADER, response::OK_JSON};
@@ -20,7 +19,6 @@ use tlsn_data_fixtures::http::{request::GET_WITH_HEADER, response::OK_JSON};
 /// Tests that the attestation protocol and verification work end-to-end
 #[test]
 fn test_api() {
-    let mut rng = StdRng::seed_from_u64(0);
     let mut provider = CryptoProvider::default();
 
     // Configure signer for Notary
@@ -28,6 +26,8 @@ fn test_api() {
 
     let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
     let (sent_len, recv_len) = transcript.len();
+    // Plaintext encodings which the Prover obtained from GC evaluation
+    let encodings_provider = fixtures::encoding_provider(GET_WITH_HEADER, OK_JSON);
 
     // At the end of the TLS connection the Prover holds the:
     let ConnectionFixture {
@@ -44,38 +44,26 @@ fn test_api() {
         unreachable!()
     };
 
-    // Create hash commitments
-    let hasher = Blake3::default();
-    let sent_blinder: Blinder = rng.random();
-    let recv_blinder: Blinder = rng.random();
+    // Prover specifies the ranges it wants to commit to.
+    let mut transcript_commitment_builder = TranscriptCommitConfigBuilder::new(&transcript);
+    transcript_commitment_builder
+        .commit_sent(&(0..sent_len))
+        .unwrap()
+        .commit_recv(&(0..recv_len))
+        .unwrap();
 
-    let sent_idx = RangeSet::from(0..sent_len);
-    let recv_idx = RangeSet::from(0..recv_len);
+    let transcripts_commitment_config = transcript_commitment_builder.build().unwrap();
 
-    let sent_hash_commitment = PlaintextHash {
-        direction: Direction::Sent,
-        idx: sent_idx.clone(),
-        hash: hash_plaintext(&hasher, transcript.sent(), &sent_blinder),
-    };
+    // Prover constructs encoding tree.
+    let encoding_tree = EncodingTree::new(
+        &Blake3::default(),
+        transcripts_commitment_config.iter_encoding(),
+        &encodings_provider,
+    )
+    .unwrap();
 
-    let recv_hash_commitment = PlaintextHash {
-        direction: Direction::Received,
-        idx: recv_idx.clone(),
-        hash: hash_plaintext(&hasher, transcript.received(), &recv_blinder),
-    };
-
-    let sent_hash_secret = PlaintextHashSecret {
-        direction: Direction::Sent,
-        idx: sent_idx,
-        alg: HashAlgId::BLAKE3,
-        blinder: sent_blinder,
-    };
-
-    let recv_hash_secret = PlaintextHashSecret {
-        direction: Direction::Received,
-        idx: recv_idx,
-        alg: HashAlgId::BLAKE3,
-        blinder: recv_blinder,
+    let encoding_commitment = EncodingCommitment {
+        root: encoding_tree.root(),
     };
 
     let request_config = RequestConfig::default();
@@ -86,14 +74,8 @@ fn test_api() {
         .handshake_data(server_cert_data)
         .transcript(transcript)
         .transcript_commitments(
-            vec![
-                TranscriptSecret::Hash(sent_hash_secret),
-                TranscriptSecret::Hash(recv_hash_secret),
-            ],
-            vec![
-                TranscriptCommitment::Hash(sent_hash_commitment.clone()),
-                TranscriptCommitment::Hash(recv_hash_commitment.clone()),
-            ],
+            vec![TranscriptSecret::Encoding(encoding_tree)],
+            vec![TranscriptCommitment::Encoding(encoding_commitment.clone())],
         );
 
     let (request, secrets) = request_builder.build(&provider).unwrap();
@@ -113,10 +95,8 @@ fn test_api() {
         .connection_info(connection_info.clone())
         // Server key Notary received during handshake
         .server_ephemeral_key(server_ephemeral_key)
-        .transcript_commitments(vec![
-            TranscriptCommitment::Hash(sent_hash_commitment),
-            TranscriptCommitment::Hash(recv_hash_commitment),
-        ]);
+        .encoder_secret(encoder_secret())
+        .transcript_commitments(vec![TranscriptCommitment::Encoding(encoding_commitment)]);
 
     let attestation = attestation_builder.build(&provider).unwrap();
 

crates/core/src/fixtures.rs

@@ -1,7 +1,10 @@
 //! Fixtures for testing
 
+mod provider;
 pub mod transcript;
 
+pub use provider::FixtureEncodingProvider;
+
 use hex::FromHex;
 
 use crate::{
@@ -10,6 +13,10 @@ use crate::{
         ServerEphemKey, ServerName, ServerSignature, SignatureAlgorithm, TlsVersion,
         TranscriptLength,
     },
+    transcript::{
+        encoding::{EncoderSecret, EncodingProvider},
+        Transcript,
+    },
     webpki::CertificateDer,
 };
 
@@ -122,3 +129,27 @@ impl ConnectionFixture {
         server_ephemeral_key
     }
 }
+
+/// Returns an encoding provider fixture.
+pub fn encoding_provider(tx: &[u8], rx: &[u8]) -> impl EncodingProvider {
+    let secret = encoder_secret();
+    FixtureEncodingProvider::new(&secret, Transcript::new(tx, rx))
+}
+
+/// Seed fixture.
+const SEED: [u8; 32] = [0; 32];
+
+/// Delta fixture.
+const DELTA: [u8; 16] = [1; 16];
+
+/// Returns an encoder secret fixture.
+pub fn encoder_secret() -> EncoderSecret {
+    EncoderSecret::new(SEED, DELTA)
+}
+
+/// Returns a tampered encoder secret fixture.
+pub fn encoder_secret_tampered_seed() -> EncoderSecret {
+    let mut seed = SEED;
+    seed[0] += 1;
+    EncoderSecret::new(seed, DELTA)
+}

crates/core/src/fixtures/provider.rs

@@ -0,0 +1,41 @@
+use std::ops::Range;
+
+use crate::transcript::{
+    encoding::{new_encoder, Encoder, EncoderSecret, EncodingProvider, EncodingProviderError},
+    Direction, Transcript,
+};
+
+/// A encoding provider fixture.
+pub struct FixtureEncodingProvider {
+    encoder: Box<dyn Encoder>,
+    transcript: Transcript,
+}
+
+impl FixtureEncodingProvider {
+    /// Creates a new encoding provider fixture.
+    pub(crate) fn new(secret: &EncoderSecret, transcript: Transcript) -> Self {
+        Self {
+            encoder: Box::new(new_encoder(secret)),
+            transcript,
+        }
+    }
+}
+
+impl EncodingProvider for FixtureEncodingProvider {
+    fn provide_encoding(
+        &self,
+        direction: Direction,
+        range: Range<usize>,
+        dest: &mut Vec<u8>,
+    ) -> Result<(), EncodingProviderError> {
+        let transcript = match direction {
+            Direction::Sent => &self.transcript.sent(),
+            Direction::Received => &self.transcript.received(),
+        };
+
+        let data = transcript.get(range.clone()).ok_or(EncodingProviderError)?;
+        self.encoder.encode_data(direction, range, data, dest);
+
+        Ok(())
+    }
+}

crates/core/src/lib.rs

@@ -19,7 +19,9 @@ use serde::{Deserialize, Serialize};
 
 use crate::{
     connection::ServerName,
-    transcript::{PartialTranscript, TranscriptCommitment, TranscriptSecret},
+    transcript::{
+        encoding::EncoderSecret, PartialTranscript, TranscriptCommitment, TranscriptSecret,
+    },
 };
 
 /// Prover output.
@@ -40,6 +42,8 @@ pub struct VerifierOutput {
     pub server_name: Option<ServerName>,
     /// Transcript data.
     pub transcript: Option<PartialTranscript>,
+    /// Encoding commitment secret.
+    pub encoder_secret: Option<EncoderSecret>,
     /// Transcript commitments.
     pub transcript_commitments: Vec<TranscriptCommitment>,
 }

crates/core/src/merkle.rs

@@ -63,6 +63,11 @@ impl MerkleProof {
 
         Ok(())
     }
+
+    /// Returns the leaf count of the Merkle tree associated with the proof.
+    pub(crate) fn leaf_count(&self) -> usize {
+        self.leaf_count
+    }
 }
 
 #[derive(Clone)]

crates/core/src/transcript.rs

@@ -19,6 +19,7 @@
 //! withheld.
 
 mod commit;
+pub mod encoding;
 pub mod hash;
 mod proof;
 mod tls;

crates/core/src/transcript/commit.rs

@@ -8,15 +8,27 @@ use serde::{Deserialize, Serialize};
 use crate::{
     hash::HashAlgId,
     transcript::{
+        encoding::{EncodingCommitment, EncodingTree},
         hash::{PlaintextHash, PlaintextHashSecret},
         Direction, RangeSet, Transcript,
     },
 };
 
+/// The maximum allowed total bytelength of committed data for a single
+/// commitment kind. Used to prevent DoS during verification. (May cause the
+/// verifier to hash up to a max of 1GB * 128 = 128GB of data for certain kinds
+/// of encoding commitments.)
+///
+/// This value must not exceed bcs's MAX_SEQUENCE_LENGTH limit (which is (1 <<
+/// 31) - 1 by default)
+pub(crate) const MAX_TOTAL_COMMITTED_DATA: usize = 1_000_000_000;
+
 /// Kind of transcript commitment.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Serialize, Deserialize)]
 #[non_exhaustive]
 pub enum TranscriptCommitmentKind {
+    /// A commitment to encodings of the transcript.
+    Encoding,
     /// A hash commitment to plaintext in the transcript.
     Hash {
         /// The hash algorithm used.
@@ -27,6 +39,7 @@ pub enum TranscriptCommitmentKind {
 impl fmt::Display for TranscriptCommitmentKind {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
+            Self::Encoding => f.write_str("encoding"),
             Self::Hash { alg } => write!(f, "hash ({alg})"),
         }
     }
@@ -36,6 +49,8 @@ impl fmt::Display for TranscriptCommitmentKind {
 #[derive(Debug, Clone, Serialize, Deserialize)]
 #[non_exhaustive]
 pub enum TranscriptCommitment {
+    /// Encoding commitment.
+    Encoding(EncodingCommitment),
     /// Plaintext hash commitment.
     Hash(PlaintextHash),
 }
@@ -44,6 +59,8 @@ pub enum TranscriptCommitment {
 #[derive(Debug, Clone, Serialize, Deserialize)]
 #[non_exhaustive]
 pub enum TranscriptSecret {
+    /// Encoding tree.
+    Encoding(EncodingTree),
     /// Plaintext hash secret.
     Hash(PlaintextHashSecret),
 }
@@ -51,6 +68,9 @@ pub enum TranscriptSecret {
 /// Configuration for transcript commitments.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct TranscriptCommitConfig {
+    encoding_hash_alg: HashAlgId,
+    has_encoding: bool,
+    has_hash: bool,
     commits: Vec<((Direction, RangeSet<usize>), TranscriptCommitmentKind)>,
 }
 
@@ -60,23 +80,53 @@ impl TranscriptCommitConfig {
         TranscriptCommitConfigBuilder::new(transcript)
     }
 
+    /// Returns the hash algorithm to use for encoding commitments.
+    pub fn encoding_hash_alg(&self) -> &HashAlgId {
+        &self.encoding_hash_alg
+    }
+
+    /// Returns `true` if the configuration has any encoding commitments.
+    pub fn has_encoding(&self) -> bool {
+        self.has_encoding
+    }
+
     /// Returns `true` if the configuration has any hash commitments.
     pub fn has_hash(&self) -> bool {
-        self.commits
-            .iter()
-            .any(|(_, kind)| matches!(kind, TranscriptCommitmentKind::Hash { .. }))
+        self.has_hash
+    }
+
+    /// Returns an iterator over the encoding commitment indices.
+    pub fn iter_encoding(&self) -> impl Iterator<Item = &(Direction, RangeSet<usize>)> {
+        self.commits.iter().filter_map(|(idx, kind)| match kind {
+            TranscriptCommitmentKind::Encoding => Some(idx),
+            _ => None,
+        })
     }
 
     /// Returns an iterator over the hash commitment indices.
     pub fn iter_hash(&self) -> impl Iterator<Item = (&(Direction, RangeSet<usize>), &HashAlgId)> {
-        self.commits.iter().map(|(idx, kind)| match kind {
-            TranscriptCommitmentKind::Hash { alg } => (idx, alg),
+        self.commits.iter().filter_map(|(idx, kind)| match kind {
+            TranscriptCommitmentKind::Hash { alg } => Some((idx, alg)),
+            _ => None,
         })
     }
 
     /// Returns a request for the transcript commitments.
     pub fn to_request(&self) -> TranscriptCommitRequest {
         TranscriptCommitRequest {
+            encoding: self.has_encoding.then(|| {
+                let mut sent = RangeSet::default();
+                let mut recv = RangeSet::default();
+
+                for (dir, idx) in self.iter_encoding() {
+                    match dir {
+                        Direction::Sent => sent.union_mut(idx),
+                        Direction::Received => recv.union_mut(idx),
+                    }
+                }
+
+                (sent, recv)
+            }),
             hash: self
                 .iter_hash()
                 .map(|((dir, idx), alg)| (*dir, idx.clone(), *alg))
@@ -86,9 +136,15 @@ impl TranscriptCommitConfig {
 }
 
 /// A builder for [`TranscriptCommitConfig`].
+///
+/// The default hash algorithm is [`HashAlgId::BLAKE3`] and the default kind
+/// is [`TranscriptCommitmentKind::Encoding`].
 #[derive(Debug)]
 pub struct TranscriptCommitConfigBuilder<'a> {
     transcript: &'a Transcript,
+    encoding_hash_alg: HashAlgId,
+    has_encoding: bool,
+    has_hash: bool,
     default_kind: TranscriptCommitmentKind,
     commits: HashSet<((Direction, RangeSet<usize>), TranscriptCommitmentKind)>,
 }
@@ -98,13 +154,20 @@ impl<'a> TranscriptCommitConfigBuilder<'a> {
     pub fn new(transcript: &'a Transcript) -> Self {
         Self {
             transcript,
-            default_kind: TranscriptCommitmentKind::Hash {
-                alg: HashAlgId::BLAKE3,
-            },
+            encoding_hash_alg: HashAlgId::BLAKE3,
+            has_encoding: false,
+            has_hash: false,
+            default_kind: TranscriptCommitmentKind::Encoding,
             commits: HashSet::default(),
         }
     }
 
+    /// Sets the hash algorithm to use for encoding commitments.
+    pub fn encoding_hash_alg(&mut self, alg: HashAlgId) -> &mut Self {
+        self.encoding_hash_alg = alg;
+        self
+    }
+
     /// Sets the default kind of commitment to use.
     pub fn default_kind(&mut self, default_kind: TranscriptCommitmentKind) -> &mut Self {
         self.default_kind = default_kind;
@@ -138,6 +201,11 @@ impl<'a> TranscriptCommitConfigBuilder<'a> {
             ));
         }
 
+        match kind {
+            TranscriptCommitmentKind::Encoding => self.has_encoding = true,
+            TranscriptCommitmentKind::Hash { .. } => self.has_hash = true,
+        }
+
         self.commits.insert(((direction, idx), kind));
 
         Ok(self)
@@ -184,6 +252,9 @@ impl<'a> TranscriptCommitConfigBuilder<'a> {
     /// Builds the configuration.
     pub fn build(self) -> Result<TranscriptCommitConfig, TranscriptCommitConfigBuilderError> {
         Ok(TranscriptCommitConfig {
+            encoding_hash_alg: self.encoding_hash_alg,
+            has_encoding: self.has_encoding,
+            has_hash: self.has_hash,
             commits: Vec::from_iter(self.commits),
         })
     }
@@ -230,10 +301,16 @@ impl fmt::Display for TranscriptCommitConfigBuilderError {
 /// Request to compute transcript commitments.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct TranscriptCommitRequest {
+    encoding: Option<(RangeSet<usize>, RangeSet<usize>)>,
     hash: Vec<(Direction, RangeSet<usize>, HashAlgId)>,
 }
 
 impl TranscriptCommitRequest {
+    /// Returns `true` if an encoding commitment is requested.
+    pub fn has_encoding(&self) -> bool {
+        self.encoding.is_some()
+    }
+
     /// Returns `true` if a hash commitment is requested.
     pub fn has_hash(&self) -> bool {
         !self.hash.is_empty()
@@ -243,6 +320,11 @@ impl TranscriptCommitRequest {
     pub fn iter_hash(&self) -> impl Iterator<Item = &(Direction, RangeSet<usize>, HashAlgId)> {
         self.hash.iter()
     }
+
+    /// Returns the ranges of the encoding commitments.
+    pub fn encoding(&self) -> Option<&(RangeSet<usize>, RangeSet<usize>)> {
+        self.encoding.as_ref()
+    }
 }
 
 #[cfg(test)]

crates/core/src/transcript/encoding.rs

@@ -0,0 +1,22 @@
+//! Transcript encoding commitments and proofs.
+
+mod encoder;
+mod proof;
+mod provider;
+mod tree;
+
+pub use encoder::{new_encoder, Encoder, EncoderSecret};
+pub use proof::{EncodingProof, EncodingProofError};
+pub use provider::{EncodingProvider, EncodingProviderError};
+pub use tree::{EncodingTree, EncodingTreeError};
+
+use serde::{Deserialize, Serialize};
+
+use crate::hash::TypedHash;
+
+/// Transcript encoding commitment.
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct EncodingCommitment {
+    /// Merkle root of the encoding commitments.
+    pub root: TypedHash,
+}

crates/core/src/transcript/encoding/encoder.rs

@@ -0,0 +1,137 @@
+use std::ops::Range;
+
+use crate::transcript::Direction;
+use itybity::ToBits;
+use rand::{RngCore, SeedableRng};
+use rand_chacha::ChaCha12Rng;
+use serde::{Deserialize, Serialize};
+
+/// The size of the encoding for 1 bit, in bytes.
+const BIT_ENCODING_SIZE: usize = 16;
+/// The size of the encoding for 1 byte, in bytes.
+const BYTE_ENCODING_SIZE: usize = 128;
+
+/// Secret used by an encoder to generate encodings.
+#[derive(Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct EncoderSecret {
+    seed: [u8; 32],
+    delta: [u8; BIT_ENCODING_SIZE],
+}
+
+opaque_debug::implement!(EncoderSecret);
+
+impl EncoderSecret {
+    /// Creates a new secret.
+    ///
+    /// # Arguments
+    ///
+    /// * `seed` - The seed for the PRG.
+    /// * `delta` - Delta for deriving the one-encodings.
+    pub fn new(seed: [u8; 32], delta: [u8; 16]) -> Self {
+        Self { seed, delta }
+    }
+
+    /// Returns the seed.
+    pub fn seed(&self) -> &[u8; 32] {
+        &self.seed
+    }
+
+    /// Returns the delta.
+    pub fn delta(&self) -> &[u8; 16] {
+        &self.delta
+    }
+}
+
+/// Creates a new encoder.
+pub fn new_encoder(secret: &EncoderSecret) -> impl Encoder {
+    ChaChaEncoder::new(secret)
+}
+
+pub(crate) struct ChaChaEncoder {
+    seed: [u8; 32],
+    delta: [u8; 16],
+}
+
+impl ChaChaEncoder {
+    pub(crate) fn new(secret: &EncoderSecret) -> Self {
+        let seed = *secret.seed();
+        let delta = *secret.delta();
+
+        Self { seed, delta }
+    }
+
+    pub(crate) fn new_prg(&self, stream_id: u64) -> ChaCha12Rng {
+        let mut prg = ChaCha12Rng::from_seed(self.seed);
+        prg.set_stream(stream_id);
+        prg.set_word_pos(0);
+        prg
+    }
+}
+
+/// A transcript encoder.
+///
+/// This is an internal implementation detail that should not be exposed to the
+/// public API.
+pub trait Encoder {
+    /// Writes the zero encoding for the given range of the transcript into the
+    /// destination buffer.
+    fn encode_range(&self, direction: Direction, range: Range<usize>, dest: &mut Vec<u8>);
+
+    /// Writes the encoding for the given data into the destination buffer.
+    fn encode_data(
+        &self,
+        direction: Direction,
+        range: Range<usize>,
+        data: &[u8],
+        dest: &mut Vec<u8>,
+    );
+}
+
+impl Encoder for ChaChaEncoder {
+    fn encode_range(&self, direction: Direction, range: Range<usize>, dest: &mut Vec<u8>) {
+        // ChaCha encoder works with 32-bit words. Each encoded bit is 128 bits long.
+        const WORDS_PER_BYTE: u128 = 8 * 128 / 32;
+
+        let stream_id: u64 = match direction {
+            Direction::Sent => 0,
+            Direction::Received => 1,
+        };
+
+        let mut prg = self.new_prg(stream_id);
+        let len = range.len() * BYTE_ENCODING_SIZE;
+        let pos = dest.len();
+
+        // Write 0s to the destination buffer.
+        dest.resize(pos + len, 0);
+
+        // Fill the destination buffer with the PRG.
+        prg.set_word_pos(range.start as u128 * WORDS_PER_BYTE);
+        prg.fill_bytes(&mut dest[pos..pos + len]);
+    }
+
+    fn encode_data(
+        &self,
+        direction: Direction,
+        range: Range<usize>,
+        data: &[u8],
+        dest: &mut Vec<u8>,
+    ) {
+        const ZERO: [u8; 16] = [0; BIT_ENCODING_SIZE];
+
+        let pos = dest.len();
+
+        // Write the zero encoding for the given range.
+        self.encode_range(direction, range, dest);
+        let dest = &mut dest[pos..];
+
+        for (pos, bit) in data.iter_lsb0().enumerate() {
+            // Add the delta to the encoding whenever the encoded bit is 1,
+            // otherwise add a zero.
+            let summand = if bit { &self.delta } else { &ZERO };
+            dest[pos * BIT_ENCODING_SIZE..(pos + 1) * BIT_ENCODING_SIZE]
+                .iter_mut()
+                .zip(summand)
+                .for_each(|(a, b)| *a ^= *b);
+        }
+    }
+}

crates/core/src/transcript/encoding/proof.rs

@@ -0,0 +1,361 @@
+use std::{collections::HashMap, fmt};
+
+use rangeset::set::RangeSet;
+use serde::{Deserialize, Serialize};
+
+use crate::{
+    hash::{Blinder, HashProvider, HashProviderError},
+    merkle::{MerkleError, MerkleProof},
+    transcript::{
+        commit::MAX_TOTAL_COMMITTED_DATA,
+        encoding::{new_encoder, Encoder, EncoderSecret, EncodingCommitment},
+        Direction,
+    },
+};
+
+/// An opening of a leaf in the encoding tree.
+#[derive(Clone, Serialize, Deserialize)]
+pub(super) struct Opening {
+    pub(super) direction: Direction,
+    pub(super) idx: RangeSet<usize>,
+    pub(super) blinder: Blinder,
+}
+
+opaque_debug::implement!(Opening);
+
+/// An encoding commitment proof.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(try_from = "validation::EncodingProofUnchecked")]
+pub struct EncodingProof {
+    /// The proof of inclusion of the commitment(s) in the Merkle tree of
+    /// commitments.
+    pub(super) inclusion_proof: MerkleProof,
+    pub(super) openings: HashMap<usize, Opening>,
+}
+
+impl EncodingProof {
+    /// Verifies the proof against the commitment.
+    ///
+    /// Returns the authenticated indices of the sent and received data,
+    /// respectively.
+    ///
+    /// # Arguments
+    ///
+    /// * `provider` - Hash provider.
+    /// * `commitment` - Encoding commitment to verify against.
+    /// * `sent` - Sent data to authenticate.
+    /// * `recv` - Received data to authenticate.
+    pub fn verify_with_provider(
+        &self,
+        provider: &HashProvider,
+        secret: &EncoderSecret,
+        commitment: &EncodingCommitment,
+        sent: &[u8],
+        recv: &[u8],
+    ) -> Result<(RangeSet<usize>, RangeSet<usize>), EncodingProofError> {
+        let hasher = provider.get(&commitment.root.alg)?;
+
+        let encoder = new_encoder(secret);
+        let Self {
+            inclusion_proof,
+            openings,
+        } = self;
+
+        let mut leaves = Vec::with_capacity(openings.len());
+        let mut expected_leaf = Vec::default();
+        let mut total_opened = 0u128;
+        let mut auth_sent = RangeSet::default();
+        let mut auth_recv = RangeSet::default();
+        for (
+            id,
+            Opening {
+                direction,
+                idx,
+                blinder,
+            },
+        ) in openings
+        {
+            // Make sure the amount of data being proved is bounded.
+            total_opened += idx.len() as u128;
+            if total_opened > MAX_TOTAL_COMMITTED_DATA as u128 {
+                return Err(EncodingProofError::new(
+                    ErrorKind::Proof,
+                    "exceeded maximum allowed data",
+                ))?;
+            }
+
+            let (data, auth) = match direction {
+                Direction::Sent => (sent, &mut auth_sent),
+                Direction::Received => (recv, &mut auth_recv),
+            };
+
+            // Make sure the ranges are within the bounds of the transcript.
+            if idx.end().unwrap_or(0) > data.len() {
+                return Err(EncodingProofError::new(
+                    ErrorKind::Proof,
+                    format!(
+                        "index out of bounds of the transcript ({}): {} > {}",
+                        direction,
+                        idx.end().unwrap_or(0),
+                        data.len()
+                    ),
+                ));
+            }
+
+            expected_leaf.clear();
+            for range in idx.iter() {
+                encoder.encode_data(*direction, range.clone(), &data[range], &mut expected_leaf);
+            }
+            expected_leaf.extend_from_slice(blinder.as_bytes());
+
+            // Compute the expected hash of the commitment to make sure it is
+            // present in the merkle tree.
+            leaves.push((*id, hasher.hash(&expected_leaf)));
+
+            auth.union_mut(idx);
+        }
+
+        // Verify that the expected hashes are present in the merkle tree.
+        //
+        // This proves the Prover committed to the purported data prior to the encoder
+        // seed being revealed. Ergo, if the encodings are authentic then the purported
+        // data is authentic.
+        inclusion_proof.verify(hasher, &commitment.root, leaves)?;
+
+        Ok((auth_sent, auth_recv))
+    }
+}
+
+/// Error for [`EncodingProof`].
+#[derive(Debug, thiserror::Error)]
+pub struct EncodingProofError {
+    kind: ErrorKind,
+    source: Option<Box<dyn std::error::Error + Send + Sync>>,
+}
+
+impl EncodingProofError {
+    fn new<E>(kind: ErrorKind, source: E) -> Self
+    where
+        E: Into<Box<dyn std::error::Error + Send + Sync>>,
+    {
+        Self {
+            kind,
+            source: Some(source.into()),
+        }
+    }
+}
+
+#[derive(Debug)]
+enum ErrorKind {
+    Provider,
+    Proof,
+}
+
+impl fmt::Display for EncodingProofError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.write_str("encoding proof error: ")?;
+
+        match self.kind {
+            ErrorKind::Provider => f.write_str("provider error")?,
+            ErrorKind::Proof => f.write_str("proof error")?,
+        }
+
+        if let Some(source) = &self.source {
+            write!(f, " caused by: {source}")?;
+        }
+
+        Ok(())
+    }
+}
+
+impl From<HashProviderError> for EncodingProofError {
+    fn from(error: HashProviderError) -> Self {
+        Self::new(ErrorKind::Provider, error)
+    }
+}
+
+impl From<MerkleError> for EncodingProofError {
+    fn from(error: MerkleError) -> Self {
+        Self::new(ErrorKind::Proof, error)
+    }
+}
+
+/// Invalid encoding proof error.
+#[derive(Debug, thiserror::Error)]
+#[error("invalid encoding proof: {0}")]
+pub struct InvalidEncodingProof(&'static str);
+
+mod validation {
+    use super::*;
+
+    /// The maximum allowed height of the Merkle tree of encoding commitments.
+    ///
+    /// The statistical security parameter (SSP) of the encoding commitment
+    /// protocol is calculated as "the number of uniformly random bits in a
+    /// single bit's encoding minus `MAX_HEIGHT`".
+    ///
+    /// For example, a bit encoding used in garbled circuits typically has 127
+    /// uniformly random bits, hence when using it in the encoding
+    /// commitment protocol, the SSP is 127 - 30 = 97 bits.
+    ///
+    /// Leaving this validation here as a fail-safe in case we ever start
+    /// using shorter encodings.
+    const MAX_HEIGHT: usize = 30;
+
+    #[derive(Debug, Deserialize)]
+    pub(super) struct EncodingProofUnchecked {
+        inclusion_proof: MerkleProof,
+        openings: HashMap<usize, Opening>,
+    }
+
+    impl TryFrom<EncodingProofUnchecked> for EncodingProof {
+        type Error = InvalidEncodingProof;
+
+        fn try_from(unchecked: EncodingProofUnchecked) -> Result<Self, Self::Error> {
+            if unchecked.inclusion_proof.leaf_count() > 1 << MAX_HEIGHT {
+                return Err(InvalidEncodingProof(
+                    "the height of the tree exceeds the maximum allowed",
+                ));
+            }
+
+            Ok(Self {
+                inclusion_proof: unchecked.inclusion_proof,
+                openings: unchecked.openings,
+            })
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use tlsn_data_fixtures::http::{request::POST_JSON, response::OK_JSON};
+
+    use crate::{
+        fixtures::{encoder_secret, encoder_secret_tampered_seed, encoding_provider},
+        hash::Blake3,
+        transcript::{encoding::EncodingTree, Transcript},
+    };
+
+    use super::*;
+
+    struct EncodingFixture {
+        transcript: Transcript,
+        proof: EncodingProof,
+        commitment: EncodingCommitment,
+    }
+
+    fn new_encoding_fixture() -> EncodingFixture {
+        let transcript = Transcript::new(POST_JSON, OK_JSON);
+
+        let idx_0 = (Direction::Sent, RangeSet::from(0..POST_JSON.len()));
+        let idx_1 = (Direction::Received, RangeSet::from(0..OK_JSON.len()));
+
+        let provider = encoding_provider(transcript.sent(), transcript.received());
+        let tree = EncodingTree::new(&Blake3::default(), [&idx_0, &idx_1], &provider).unwrap();
+
+        let proof = tree.proof([&idx_0, &idx_1].into_iter()).unwrap();
+
+        let commitment = EncodingCommitment { root: tree.root() };
+
+        EncodingFixture {
+            transcript,
+            proof,
+            commitment,
+        }
+    }
+
+    #[test]
+    fn test_verify_encoding_proof_tampered_seed() {
+        let EncodingFixture {
+            transcript,
+            proof,
+            commitment,
+        } = new_encoding_fixture();
+
+        let err = proof
+            .verify_with_provider(
+                &HashProvider::default(),
+                &encoder_secret_tampered_seed(),
+                &commitment,
+                transcript.sent(),
+                transcript.received(),
+            )
+            .unwrap_err();
+
+        assert!(matches!(err.kind, ErrorKind::Proof));
+    }
+
+    #[test]
+    fn test_verify_encoding_proof_out_of_range() {
+        let EncodingFixture {
+            transcript,
+            proof,
+            commitment,
+        } = new_encoding_fixture();
+
+        let sent = &transcript.sent()[transcript.sent().len() - 1..];
+        let recv = &transcript.received()[transcript.received().len() - 2..];
+
+        let err = proof
+            .verify_with_provider(
+                &HashProvider::default(),
+                &encoder_secret(),
+                &commitment,
+                sent,
+                recv,
+            )
+            .unwrap_err();
+
+        assert!(matches!(err.kind, ErrorKind::Proof));
+    }
+
+    #[test]
+    fn test_verify_encoding_proof_tampered_idx() {
+        let EncodingFixture {
+            transcript,
+            mut proof,
+            commitment,
+        } = new_encoding_fixture();
+
+        let Opening { idx, .. } = proof.openings.values_mut().next().unwrap();
+
+        *idx = RangeSet::from([0..3, 13..15]);
+
+        let err = proof
+            .verify_with_provider(
+                &HashProvider::default(),
+                &encoder_secret(),
+                &commitment,
+                transcript.sent(),
+                transcript.received(),
+            )
+            .unwrap_err();
+
+        assert!(matches!(err.kind, ErrorKind::Proof));
+    }
+
+    #[test]
+    fn test_verify_encoding_proof_tampered_encoding_blinder() {
+        let EncodingFixture {
+            transcript,
+            mut proof,
+            commitment,
+        } = new_encoding_fixture();
+
+        let Opening { blinder, .. } = proof.openings.values_mut().next().unwrap();
+
+        *blinder = rand::random();
+
+        let err = proof
+            .verify_with_provider(
+                &HashProvider::default(),
+                &encoder_secret(),
+                &commitment,
+                transcript.sent(),
+                transcript.received(),
+            )
+            .unwrap_err();
+
+        assert!(matches!(err.kind, ErrorKind::Proof));
+    }
+}

crates/core/src/transcript/encoding/provider.rs

@@ -0,0 +1,19 @@
+use std::ops::Range;
+
+use crate::transcript::Direction;
+
+/// A provider of plaintext encodings.
+pub trait EncodingProvider {
+    /// Writes the encoding of the given range into the destination buffer.
+    fn provide_encoding(
+        &self,
+        direction: Direction,
+        range: Range<usize>,
+        dest: &mut Vec<u8>,
+    ) -> Result<(), EncodingProviderError>;
+}
+
+/// Error for [`EncodingProvider`].
+#[derive(Debug, thiserror::Error)]
+#[error("failed to provide encoding")]
+pub struct EncodingProviderError;

crates/core/src/transcript/encoding/tree.rs

@@ -0,0 +1,327 @@
+use std::collections::HashMap;
+
+use bimap::BiMap;
+use rangeset::set::RangeSet;
+use serde::{Deserialize, Serialize};
+
+use crate::{
+    hash::{Blinder, HashAlgId, HashAlgorithm, TypedHash},
+    merkle::MerkleTree,
+    transcript::{
+        encoding::{
+            proof::{EncodingProof, Opening},
+            EncodingProvider,
+        },
+        Direction,
+    },
+};
+
+/// Encoding tree builder error.
+#[derive(Debug, thiserror::Error)]
+pub enum EncodingTreeError {
+    /// Index is out of bounds of the transcript.
+    #[error("index is out of bounds of the transcript")]
+    OutOfBounds {
+        /// The index.
+        index: RangeSet<usize>,
+        /// The transcript length.
+        transcript_length: usize,
+    },
+    /// Encoding provider is missing an encoding for an index.
+    #[error("encoding provider is missing an encoding for an index")]
+    MissingEncoding {
+        /// The index which is missing.
+        index: RangeSet<usize>,
+    },
+    /// Index is missing from the tree.
+    #[error("index is missing from the tree")]
+    MissingLeaf {
+        /// The index which is missing.
+        index: RangeSet<usize>,
+    },
+}
+
+/// A merkle tree of transcript encodings.
+#[derive(Clone, Serialize, Deserialize)]
+pub struct EncodingTree {
+    /// Merkle tree of the commitments.
+    tree: MerkleTree,
+    /// Nonces used to blind the hashes.
+    blinders: Vec<Blinder>,
+    /// Mapping between the index of a leaf and the transcript index it
+    /// corresponds to.
+    idxs: BiMap<usize, (Direction, RangeSet<usize>)>,
+    /// Union of all transcript indices in the sent direction.
+    sent_idx: RangeSet<usize>,
+    /// Union of all transcript indices in the received direction.
+    received_idx: RangeSet<usize>,
+}
+
+opaque_debug::implement!(EncodingTree);
+
+impl EncodingTree {
+    /// Creates a new encoding tree.
+    ///
+    /// # Arguments
+    ///
+    /// * `hasher` - The hash algorithm to use.
+    /// * `idxs` - The subsequence indices to commit to.
+    /// * `provider` - The encoding provider.
+    pub fn new<'idx>(
+        hasher: &dyn HashAlgorithm,
+        idxs: impl IntoIterator<Item = &'idx (Direction, RangeSet<usize>)>,
+        provider: &dyn EncodingProvider,
+    ) -> Result<Self, EncodingTreeError> {
+        let mut this = Self {
+            tree: MerkleTree::new(hasher.id()),
+            blinders: Vec::new(),
+            idxs: BiMap::new(),
+            sent_idx: RangeSet::default(),
+            received_idx: RangeSet::default(),
+        };
+
+        let mut leaves = Vec::new();
+        let mut encoding = Vec::new();
+        for dir_idx in idxs {
+            let direction = dir_idx.0;
+            let idx = &dir_idx.1;
+
+            // Ignore empty indices.
+            if idx.is_empty() {
+                continue;
+            }
+
+            if this.idxs.contains_right(dir_idx) {
+                // The subsequence is already in the tree.
+                continue;
+            }
+
+            let blinder: Blinder = rand::random();
+
+            encoding.clear();
+            for range in idx.iter() {
+                provider
+                    .provide_encoding(direction, range, &mut encoding)
+                    .map_err(|_| EncodingTreeError::MissingEncoding { index: idx.clone() })?;
+            }
+            encoding.extend_from_slice(blinder.as_bytes());
+
+            let leaf = hasher.hash(&encoding);
+
+            leaves.push(leaf);
+            this.blinders.push(blinder);
+            this.idxs.insert(this.idxs.len(), dir_idx.clone());
+            match direction {
+                Direction::Sent => this.sent_idx.union_mut(idx),
+                Direction::Received => this.received_idx.union_mut(idx),
+            }
+        }
+
+        this.tree.insert(hasher, leaves);
+
+        Ok(this)
+    }
+
+    /// Returns the root of the tree.
+    pub fn root(&self) -> TypedHash {
+        self.tree.root()
+    }
+
+    /// Returns the hash algorithm of the tree.
+    pub fn algorithm(&self) -> HashAlgId {
+        self.tree.algorithm()
+    }
+
+    /// Generates a proof for the given indices.
+    ///
+    /// # Arguments
+    ///
+    /// * `idxs` - The transcript indices to prove.
+    pub fn proof<'idx>(
+        &self,
+        idxs: impl Iterator<Item = &'idx (Direction, RangeSet<usize>)>,
+    ) -> Result<EncodingProof, EncodingTreeError> {
+        let mut openings = HashMap::new();
+        for dir_idx in idxs {
+            let direction = dir_idx.0;
+            let idx = &dir_idx.1;
+
+            let leaf_idx = *self
+                .idxs
+                .get_by_right(dir_idx)
+                .ok_or_else(|| EncodingTreeError::MissingLeaf { index: idx.clone() })?;
+            let blinder = self.blinders[leaf_idx].clone();
+
+            openings.insert(
+                leaf_idx,
+                Opening {
+                    direction,
+                    idx: idx.clone(),
+                    blinder,
+                },
+            );
+        }
+
+        let mut indices = openings.keys().copied().collect::<Vec<_>>();
+        indices.sort();
+
+        Ok(EncodingProof {
+            inclusion_proof: self.tree.proof(&indices),
+            openings,
+        })
+    }
+
+    /// Returns whether the tree contains the given transcript index.
+    pub fn contains(&self, idx: &(Direction, RangeSet<usize>)) -> bool {
+        self.idxs.contains_right(idx)
+    }
+
+    pub(crate) fn idx(&self, direction: Direction) -> &RangeSet<usize> {
+        match direction {
+            Direction::Sent => &self.sent_idx,
+            Direction::Received => &self.received_idx,
+        }
+    }
+
+    /// Returns the committed transcript indices.
+    pub(crate) fn transcript_indices(&self) -> impl Iterator<Item = &(Direction, RangeSet<usize>)> {
+        self.idxs.right_values()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::{
+        fixtures::{encoder_secret, encoding_provider},
+        hash::{Blake3, HashProvider},
+        transcript::{encoding::EncodingCommitment, Transcript},
+    };
+    use tlsn_data_fixtures::http::{request::POST_JSON, response::OK_JSON};
+
+    fn new_tree<'seq>(
+        transcript: &Transcript,
+        idxs: impl Iterator<Item = &'seq (Direction, RangeSet<usize>)>,
+    ) -> Result<EncodingTree, EncodingTreeError> {
+        let provider = encoding_provider(transcript.sent(), transcript.received());
+
+        EncodingTree::new(&Blake3::default(), idxs, &provider)
+    }
+
+    #[test]
+    fn test_encoding_tree() {
+        let transcript = Transcript::new(POST_JSON, OK_JSON);
+
+        let idx_0 = (Direction::Sent, RangeSet::from(0..POST_JSON.len()));
+        let idx_1 = (Direction::Received, RangeSet::from(0..OK_JSON.len()));
+
+        let tree = new_tree(&transcript, [&idx_0, &idx_1].into_iter()).unwrap();
+
+        assert!(tree.contains(&idx_0));
+        assert!(tree.contains(&idx_1));
+
+        let proof = tree.proof([&idx_0, &idx_1].into_iter()).unwrap();
+
+        let commitment = EncodingCommitment { root: tree.root() };
+
+        let (auth_sent, auth_recv) = proof
+            .verify_with_provider(
+                &HashProvider::default(),
+                &encoder_secret(),
+                &commitment,
+                transcript.sent(),
+                transcript.received(),
+            )
+            .unwrap();
+
+        assert_eq!(auth_sent, idx_0.1);
+        assert_eq!(auth_recv, idx_1.1);
+    }
+
+    #[test]
+    fn test_encoding_tree_multiple_ranges() {
+        let transcript = Transcript::new(POST_JSON, OK_JSON);
+
+        let idx_0 = (Direction::Sent, RangeSet::from(0..1));
+        let idx_1 = (Direction::Sent, RangeSet::from(1..POST_JSON.len()));
+        let idx_2 = (Direction::Received, RangeSet::from(0..1));
+        let idx_3 = (Direction::Received, RangeSet::from(1..OK_JSON.len()));
+
+        let tree = new_tree(&transcript, [&idx_0, &idx_1, &idx_2, &idx_3].into_iter()).unwrap();
+
+        assert!(tree.contains(&idx_0));
+        assert!(tree.contains(&idx_1));
+        assert!(tree.contains(&idx_2));
+        assert!(tree.contains(&idx_3));
+
+        let proof = tree
+            .proof([&idx_0, &idx_1, &idx_2, &idx_3].into_iter())
+            .unwrap();
+
+        let commitment = EncodingCommitment { root: tree.root() };
+
+        let (auth_sent, auth_recv) = proof
+            .verify_with_provider(
+                &HashProvider::default(),
+                &encoder_secret(),
+                &commitment,
+                transcript.sent(),
+                transcript.received(),
+            )
+            .unwrap();
+
+        let mut expected_auth_sent = RangeSet::default();
+        expected_auth_sent.union_mut(&idx_0.1);
+        expected_auth_sent.union_mut(&idx_1.1);
+
+        let mut expected_auth_recv = RangeSet::default();
+        expected_auth_recv.union_mut(&idx_2.1);
+        expected_auth_recv.union_mut(&idx_3.1);
+
+        assert_eq!(auth_sent, expected_auth_sent);
+        assert_eq!(auth_recv, expected_auth_recv);
+    }
+
+    #[test]
+    fn test_encoding_tree_proof_missing_leaf() {
+        let transcript = Transcript::new(POST_JSON, OK_JSON);
+
+        let idx_0 = (Direction::Sent, RangeSet::from(0..POST_JSON.len()));
+        let idx_1 = (Direction::Received, RangeSet::from(0..4));
+        let idx_2 = (Direction::Received, RangeSet::from(4..OK_JSON.len()));
+
+        let tree = new_tree(&transcript, [&idx_0, &idx_1].into_iter()).unwrap();
+
+        let result = tree
+            .proof([&idx_0, &idx_1, &idx_2].into_iter())
+            .unwrap_err();
+        assert!(matches!(result, EncodingTreeError::MissingLeaf { .. }));
+    }
+
+    #[test]
+    fn test_encoding_tree_out_of_bounds() {
+        let transcript = Transcript::new(POST_JSON, OK_JSON);
+
+        let idx_0 = (Direction::Sent, RangeSet::from(0..POST_JSON.len() + 1));
+        let idx_1 = (Direction::Received, RangeSet::from(0..OK_JSON.len() + 1));
+
+        let result = new_tree(&transcript, [&idx_0].into_iter()).unwrap_err();
+        assert!(matches!(result, EncodingTreeError::MissingEncoding { .. }));
+
+        let result = new_tree(&transcript, [&idx_1].into_iter()).unwrap_err();
+        assert!(matches!(result, EncodingTreeError::MissingEncoding { .. }));
+    }
+
+    #[test]
+    fn test_encoding_tree_missing_encoding() {
+        let provider = encoding_provider(&[], &[]);
+
+        let result = EncodingTree::new(
+            &Blake3::default(),
+            [(Direction::Sent, RangeSet::from(0..8))].iter(),
+            &provider,
+        )
+        .unwrap_err();
+        assert!(matches!(result, EncodingTreeError::MissingEncoding { .. }));
+    }
+}

crates/core/src/transcript/proof.rs

@@ -14,6 +14,7 @@ use crate::{
     hash::{HashAlgId, HashProvider},
     transcript::{
         commit::{TranscriptCommitment, TranscriptCommitmentKind},
+        encoding::{EncoderSecret, EncodingProof, EncodingProofError, EncodingTree},
         hash::{hash_plaintext, PlaintextHash, PlaintextHashSecret},
         Direction, PartialTranscript, RangeSet, Transcript, TranscriptSecret,
     },
@@ -31,12 +32,14 @@ const DEFAULT_COMMITMENT_KINDS: &[TranscriptCommitmentKind] = &[
     TranscriptCommitmentKind::Hash {
         alg: HashAlgId::KECCAK256,
     },
+    TranscriptCommitmentKind::Encoding,
 ];
 
 /// Proof of the contents of a transcript.
 #[derive(Clone, Serialize, Deserialize)]
 pub struct TranscriptProof {
     transcript: PartialTranscript,
+    encoding_proof: Option<EncodingProof>,
     hash_secrets: Vec<PlaintextHashSecret>,
 }
 
@@ -50,18 +53,27 @@ impl TranscriptProof {
     /// # Arguments
     ///
     /// * `provider` - The hash provider to use for verification.
-    /// * `length` - The transcript length.
-    /// * `commitments` - The commitments to verify against.
+    /// * `attestation_body` - The attestation body to verify against.
     pub fn verify_with_provider<'a>(
         self,
         provider: &HashProvider,
         length: &TranscriptLength,
+        encoder_secret: Option<&EncoderSecret>,
         commitments: impl IntoIterator<Item = &'a TranscriptCommitment>,
     ) -> Result<PartialTranscript, TranscriptProofError> {
+        let mut encoding_commitment = None;
         let mut hash_commitments = HashSet::new();
         // Index commitments.
         for commitment in commitments {
             match commitment {
+                TranscriptCommitment::Encoding(commitment) => {
+                    if encoding_commitment.replace(commitment).is_some() {
+                        return Err(TranscriptProofError::new(
+                            ErrorKind::Encoding,
+                            "multiple encoding commitments are present.",
+                        ));
+                    }
+                }
                 TranscriptCommitment::Hash(plaintext_hash) => {
                     hash_commitments.insert(plaintext_hash);
                 }
@@ -80,6 +92,34 @@ impl TranscriptProof {
         let mut total_auth_sent = RangeSet::default();
         let mut total_auth_recv = RangeSet::default();
 
+        // Verify encoding proof.
+        if let Some(proof) = self.encoding_proof {
+            let secret = encoder_secret.ok_or_else(|| {
+                TranscriptProofError::new(
+                    ErrorKind::Encoding,
+                    "contains an encoding proof but missing encoder secret",
+                )
+            })?;
+
+            let commitment = encoding_commitment.ok_or_else(|| {
+                TranscriptProofError::new(
+                    ErrorKind::Encoding,
+                    "contains an encoding proof but missing encoding commitment",
+                )
+            })?;
+
+            let (auth_sent, auth_recv) = proof.verify_with_provider(
+                provider,
+                secret,
+                commitment,
+                self.transcript.sent_unsafe(),
+                self.transcript.received_unsafe(),
+            )?;
+
+            total_auth_sent.union_mut(&auth_sent);
+            total_auth_recv.union_mut(&auth_recv);
+        }
+
         let mut buffer = Vec::new();
         for PlaintextHashSecret {
             direction,
@@ -163,6 +203,7 @@ impl TranscriptProofError {
 
 #[derive(Debug)]
 enum ErrorKind {
+    Encoding,
     Hash,
     Proof,
 }
@@ -172,6 +213,7 @@ impl fmt::Display for TranscriptProofError {
         f.write_str("transcript proof error: ")?;
 
         match self.kind {
+            ErrorKind::Encoding => f.write_str("encoding error")?,
             ErrorKind::Hash => f.write_str("hash error")?,
             ErrorKind::Proof => f.write_str("proof error")?,
         }
@@ -184,6 +226,12 @@ impl fmt::Display for TranscriptProofError {
     }
 }
 
+impl From<EncodingProofError> for TranscriptProofError {
+    fn from(e: EncodingProofError) -> Self {
+        TranscriptProofError::new(ErrorKind::Encoding, e)
+    }
+}
+
 /// Union of ranges to reveal.
 #[derive(Clone, Debug, PartialEq)]
 struct QueryIdx {
@@ -228,6 +276,7 @@ pub struct TranscriptProofBuilder<'a> {
     /// Commitment kinds in order of preference for building transcript proofs.
     commitment_kinds: Vec<TranscriptCommitmentKind>,
     transcript: &'a Transcript,
+    encoding_tree: Option<&'a EncodingTree>,
     hash_secrets: Vec<&'a PlaintextHashSecret>,
     committed_sent: RangeSet<usize>,
     committed_recv: RangeSet<usize>,
@@ -243,9 +292,15 @@ impl<'a> TranscriptProofBuilder<'a> {
         let mut committed_sent = RangeSet::default();
         let mut committed_recv = RangeSet::default();
 
+        let mut encoding_tree = None;
         let mut hash_secrets = Vec::new();
         for secret in secrets {
             match secret {
+                TranscriptSecret::Encoding(tree) => {
+                    committed_sent.union_mut(tree.idx(Direction::Sent));
+                    committed_recv.union_mut(tree.idx(Direction::Received));
+                    encoding_tree = Some(tree);
+                }
                 TranscriptSecret::Hash(hash) => {
                     match hash.direction {
                         Direction::Sent => committed_sent.union_mut(&hash.idx),
@@ -259,6 +314,7 @@ impl<'a> TranscriptProofBuilder<'a> {
         Self {
             commitment_kinds: DEFAULT_COMMITMENT_KINDS.to_vec(),
             transcript,
+            encoding_tree,
             hash_secrets,
             committed_sent,
             committed_recv,
@@ -356,6 +412,7 @@ impl<'a> TranscriptProofBuilder<'a> {
             transcript: self
                 .transcript
                 .to_partial(self.query_idx.sent.clone(), self.query_idx.recv.clone()),
+            encoding_proof: None,
             hash_secrets: Vec::new(),
         };
         let mut uncovered_query_idx = self.query_idx.clone();
@@ -367,6 +424,46 @@ impl<'a> TranscriptProofBuilder<'a> {
             // self.commitment_kinds.
             if let Some(kind) = commitment_kinds_iter.next() {
                 match kind {
+                    TranscriptCommitmentKind::Encoding => {
+                        let Some(encoding_tree) = self.encoding_tree else {
+                            // Proceeds to the next preferred commitment kind if encoding tree is
+                            // not available.
+                            continue;
+                        };
+
+                        let (sent_dir_idxs, sent_uncovered) = uncovered_query_idx.sent.cover_by(
+                            encoding_tree
+                                .transcript_indices()
+                                .filter(|(dir, _)| *dir == Direction::Sent),
+                            |(_, idx)| idx,
+                        );
+                        // Uncovered ranges will be checked with ranges of the next
+                        // preferred commitment kind.
+                        uncovered_query_idx.sent = sent_uncovered;
+
+                        let (recv_dir_idxs, recv_uncovered) = uncovered_query_idx.recv.cover_by(
+                            encoding_tree
+                                .transcript_indices()
+                                .filter(|(dir, _)| *dir == Direction::Received),
+                            |(_, idx)| idx,
+                        );
+                        uncovered_query_idx.recv = recv_uncovered;
+
+                        let dir_idxs = sent_dir_idxs
+                            .into_iter()
+                            .chain(recv_dir_idxs)
+                            .collect::<Vec<_>>();
+
+                        // Skip proof generation if there are no committed ranges that can cover the
+                        // query ranges.
+                        if !dir_idxs.is_empty() {
+                            transcript_proof.encoding_proof = Some(
+                                encoding_tree
+                                    .proof(dir_idxs.into_iter())
+                                    .expect("subsequences were checked to be in tree"),
+                            );
+                        }
+                    }
                     TranscriptCommitmentKind::Hash { alg } => {
                         let (sent_hashes, sent_uncovered) = uncovered_query_idx.sent.cover_by(
                             self.hash_secrets.iter().filter(|hash| {
@@ -493,10 +590,46 @@ mod tests {
     use rstest::rstest;
     use tlsn_data_fixtures::http::{request::GET_WITH_HEADER, response::OK_JSON};
 
-    use crate::hash::{Blinder, HashAlgId};
+    use crate::{
+        fixtures::{encoder_secret, encoding_provider},
+        hash::{Blake3, Blinder, HashAlgId},
+        transcript::TranscriptCommitConfigBuilder,
+    };
 
     use super::*;
 
+    #[rstest]
+    fn test_verify_missing_encoding_commitment_root() {
+        let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
+        let idxs = vec![(Direction::Received, RangeSet::from(0..transcript.len().1))];
+        let encoding_tree = EncodingTree::new(
+            &Blake3::default(),
+            &idxs,
+            &encoding_provider(transcript.sent(), transcript.received()),
+        )
+        .unwrap();
+
+        let secrets = vec![TranscriptSecret::Encoding(encoding_tree)];
+        let mut builder = TranscriptProofBuilder::new(&transcript, &secrets);
+
+        builder.reveal_recv(&(0..transcript.len().1)).unwrap();
+
+        let transcript_proof = builder.build().unwrap();
+
+        let provider = HashProvider::default();
+        let err = transcript_proof
+            .verify_with_provider(
+                &provider,
+                &transcript.length(),
+                Some(&encoder_secret()),
+                &[],
+            )
+            .err()
+            .unwrap();
+
+        assert!(matches!(err.kind, ErrorKind::Encoding));
+    }
+
     #[rstest]
     fn test_reveal_range_out_of_bounds() {
         let transcript = Transcript::new(
@@ -516,7 +649,7 @@ mod tests {
     }
 
     #[rstest]
-    fn test_reveal_missing_commitment() {
+    fn test_reveal_missing_encoding_tree() {
         let transcript = Transcript::new(
             [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11],
             [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11],
@@ -565,6 +698,7 @@ mod tests {
             .verify_with_provider(
                 &provider,
                 &transcript.length(),
+                None,
                 &[TranscriptCommitment::Hash(commitment)],
             )
             .unwrap();
@@ -614,6 +748,7 @@ mod tests {
             .verify_with_provider(
                 &provider,
                 &transcript.length(),
+                None,
                 &[TranscriptCommitment::Hash(commitment)],
             )
             .unwrap_err();
@@ -629,19 +764,24 @@ mod tests {
             TranscriptCommitmentKind::Hash {
                 alg: HashAlgId::SHA256,
             },
+            TranscriptCommitmentKind::Encoding,
             TranscriptCommitmentKind::Hash {
                 alg: HashAlgId::SHA256,
             },
             TranscriptCommitmentKind::Hash {
                 alg: HashAlgId::SHA256,
             },
+            TranscriptCommitmentKind::Encoding,
         ]);
 
         assert_eq!(
             builder.commitment_kinds,
-            vec![TranscriptCommitmentKind::Hash {
-                alg: HashAlgId::SHA256
-            },]
+            vec![
+                TranscriptCommitmentKind::Hash {
+                    alg: HashAlgId::SHA256
+                },
+                TranscriptCommitmentKind::Encoding
+            ]
         );
     }
 
@@ -651,7 +791,7 @@ mod tests {
         RangeSet::from([0..10, 12..30]),
         true,
     )]
-    #[case::reveal_all_rangesets_with_single_superset_range(
+    #[case::reveal_all_rangesets_with_superset_ranges(
         vec![RangeSet::from([0..1]), RangeSet::from([1..2, 8..9]), RangeSet::from([2..4, 6..8]), RangeSet::from([2..3, 6..7]), RangeSet::from([9..12])],
         RangeSet::from([0..4, 6..9]),
         true,
@@ -682,30 +822,29 @@ mod tests {
         false,
     )]
     #[allow(clippy::single_range_in_vec_init)]
-    fn test_reveal_multiple_rangesets_with_one_rangeset(
+    fn test_reveal_mutliple_rangesets_with_one_rangeset(
         #[case] commit_recv_rangesets: Vec<RangeSet<usize>>,
         #[case] reveal_recv_rangeset: RangeSet<usize>,
         #[case] success: bool,
     ) {
-        use rand::{Rng, SeedableRng};
-
-        let mut rng = rand::rngs::StdRng::seed_from_u64(0);
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
 
-        // Create hash commitments for each rangeset
-        let mut secrets = Vec::new();
+        // Encoding commitment kind
+        let mut transcript_commitment_builder = TranscriptCommitConfigBuilder::new(&transcript);
         for rangeset in commit_recv_rangesets.iter() {
-            let blinder: crate::hash::Blinder = rng.random();
-
-            let secret = PlaintextHashSecret {
-                direction: Direction::Received,
-                idx: rangeset.clone(),
-                alg: HashAlgId::BLAKE3,
-                blinder,
-            };
-            secrets.push(TranscriptSecret::Hash(secret));
+            transcript_commitment_builder.commit_recv(rangeset).unwrap();
         }
 
+        let transcripts_commitment_config = transcript_commitment_builder.build().unwrap();
+
+        let encoding_tree = EncodingTree::new(
+            &Blake3::default(),
+            transcripts_commitment_config.iter_encoding(),
+            &encoding_provider(GET_WITH_HEADER, OK_JSON),
+        )
+        .unwrap();
+
+        let secrets = vec![TranscriptSecret::Encoding(encoding_tree)];
         let mut builder = TranscriptProofBuilder::new(&transcript, &secrets);
 
         if success {
@@ -758,34 +897,27 @@ mod tests {
         #[case] uncovered_sent_rangeset: RangeSet<usize>,
         #[case] uncovered_recv_rangeset: RangeSet<usize>,
     ) {
-        use rand::{Rng, SeedableRng};
-
-        let mut rng = rand::rngs::StdRng::seed_from_u64(0);
         let transcript = Transcript::new(GET_WITH_HEADER, OK_JSON);
 
-        // Create hash commitments for each rangeset
-        let mut secrets = Vec::new();
+        // Encoding commitment kind
+        let mut transcript_commitment_builder = TranscriptCommitConfigBuilder::new(&transcript);
         for rangeset in commit_sent_rangesets.iter() {
-            let blinder: crate::hash::Blinder = rng.random();
-            let secret = PlaintextHashSecret {
-                direction: Direction::Sent,
-                idx: rangeset.clone(),
-                alg: HashAlgId::BLAKE3,
-                blinder,
-            };
-            secrets.push(TranscriptSecret::Hash(secret));
+            transcript_commitment_builder.commit_sent(rangeset).unwrap();
         }
         for rangeset in commit_recv_rangesets.iter() {
-            let blinder: crate::hash::Blinder = rng.random();
-            let secret = PlaintextHashSecret {
-                direction: Direction::Received,
-                idx: rangeset.clone(),
-                alg: HashAlgId::BLAKE3,
-                blinder,
-            };
-            secrets.push(TranscriptSecret::Hash(secret));
+            transcript_commitment_builder.commit_recv(rangeset).unwrap();
         }
 
+        let transcripts_commitment_config = transcript_commitment_builder.build().unwrap();
+
+        let encoding_tree = EncodingTree::new(
+            &Blake3::default(),
+            transcripts_commitment_config.iter_encoding(),
+            &encoding_provider(GET_WITH_HEADER, OK_JSON),
+        )
+        .unwrap();
+
+        let secrets = vec![TranscriptSecret::Encoding(encoding_tree)];
         let mut builder = TranscriptProofBuilder::new(&transcript, &secrets);
         builder.reveal_sent(&reveal_sent_rangeset).unwrap();
         builder.reveal_recv(&reveal_recv_rangeset).unwrap();

crates/examples/attestation/prove.rs

@@ -332,6 +332,7 @@ async fn notary<S: AsyncWrite + AsyncRead + Send + Sync + Unpin + 'static>(
     let (
         VerifierOutput {
             transcript_commitments,
+            encoder_secret,
             ..
         },
         verifier,
@@ -392,6 +393,10 @@ async fn notary<S: AsyncWrite + AsyncRead + Send + Sync + Unpin + 'static>(
         .server_ephemeral_key(tls_transcript.server_ephemeral_key().clone())
         .transcript_commitments(transcript_commitments);
 
+    if let Some(encoder_secret) = encoder_secret {
+        builder.encoder_secret(encoder_secret);
+    }
+
     let attestation = builder.build(&provider)?;
 
     // Send attestation to prover.

crates/harness/bench.toml

@@ -1,59 +1,51 @@
-#### Default Representative Benchmarks ####
-#
-# This benchmark measures TLSNotary performance on three representative network scenarios.
-# Each scenario is run multiple times to produce statistical metrics (median, std dev, etc.)
-# rather than plots. Use this for quick performance checks and CI regression testing.
-#
-# Payload sizes:
-#   - upload-size: 1KB (typical HTTP request)
-#   - download-size: 2KB (typical HTTP response/API data)
-#
-# Network scenarios are chosen to represent real-world user conditions where
-# TLSNotary is primarily bottlenecked by upload bandwidth.
-
-#### Cable/DSL Home Internet ####
-# Most common residential internet connection
-# - Asymmetric: high download, limited upload (typical bottleneck)
-# - Upload bandwidth: 20 Mbps (realistic cable/DSL upload speed)
-# - Latency: 20ms (typical ISP latency)
+#### Latency ####
 
 [[group]]
-name = "cable"
-bandwidth = 20
-protocol_latency = 20
-upload-size = 1024
-download-size = 2048
+name = "latency"
+bandwidth = 1000
 
 [[bench]]
-group = "cable"
-
-#### Mobile 5G ####
-# Modern mobile connection with good coverage
-# - Upload bandwidth: 30 Mbps (typical 5G upload in good conditions)
-# - Latency: 30ms (higher than wired due to mobile tower hops)
-
-[[group]]
-name = "mobile_5g"
-bandwidth = 30
-protocol_latency = 30
-upload-size = 1024
-download-size = 2048
+group = "latency"
+protocol_latency = 10
 
 [[bench]]
-group = "mobile_5g"
+group = "latency"
+protocol_latency = 25
 
-#### Fiber Home Internet ####
-# High-end residential connection (best case scenario)
-# - Symmetric: equal upload/download bandwidth
-# - Upload bandwidth: 100 Mbps (typical fiber upload)
-# - Latency: 15ms (lower latency than cable)
+[[bench]]
+group = "latency"
+protocol_latency = 50
+
+[[bench]]
+group = "latency"
+protocol_latency = 100
+
+[[bench]]
+group = "latency"
+protocol_latency = 200
+
+#### Bandwidth ####
 
 [[group]]
-name = "fiber"
+name = "bandwidth"
+protocol_latency = 25
+
+[[bench]]
+group = "bandwidth"
+bandwidth = 10
+
+[[bench]]
+group = "bandwidth"
+bandwidth = 50
+
+[[bench]]
+group = "bandwidth"
 bandwidth = 100
-protocol_latency = 15
-upload-size = 1024
-download-size = 2048
 
 [[bench]]
-group = "fiber"
+group = "bandwidth"
+bandwidth = 250
+
+[[bench]]
+group = "bandwidth"
+bandwidth = 1000

crates/harness/bench_bandwidth_sweep.toml

@@ -1,52 +0,0 @@
-#### Bandwidth Sweep Benchmark ####
-#
-# Measures how network bandwidth affects TLSNotary runtime.
-# Keeps latency and payload sizes fixed while varying upload bandwidth.
-#
-# Fixed parameters:
-#   - Latency: 25ms (typical internet latency)
-#   - Upload: 1KB (typical request)
-#   - Download: 2KB (typical response)
-#
-# Variable: Bandwidth from 5 Mbps to 1000 Mbps
-#
-# Use this to plot "Bandwidth vs Runtime" and understand bandwidth sensitivity.
-# Focus on upload bandwidth as TLSNotary is primarily upload-bottlenecked
-
-[[group]]
-name = "bandwidth_sweep"
-protocol_latency = 25
-upload-size = 1024
-download-size = 2048
-
-[[bench]]
-group = "bandwidth_sweep"
-bandwidth = 5
-
-[[bench]]
-group = "bandwidth_sweep"
-bandwidth = 10
-
-[[bench]]
-group = "bandwidth_sweep"
-bandwidth = 20
-
-[[bench]]
-group = "bandwidth_sweep"
-bandwidth = 50
-
-[[bench]]
-group = "bandwidth_sweep"
-bandwidth = 100
-
-[[bench]]
-group = "bandwidth_sweep"
-bandwidth = 250
-
-[[bench]]
-group = "bandwidth_sweep"
-bandwidth = 500
-
-[[bench]]
-group = "bandwidth_sweep"
-bandwidth = 1000

crates/harness/bench_download_sweep.toml

@@ -1,53 +0,0 @@
-#### Download Size Sweep Benchmark ####
-#
-# Measures how download payload size affects TLSNotary runtime.
-# Keeps network conditions fixed while varying the response size.
-#
-# Fixed parameters:
-#   - Bandwidth: 100 Mbps (typical good connection)
-#   - Latency: 25ms (typical internet latency)
-#   - Upload: 1KB (typical request size)
-#
-# Variable: Download size from 1KB to 100KB
-#
-# Use this to plot "Download Size vs Runtime" and understand how much data
-# TLSNotary can efficiently notarize. Useful for determining optimal
-# chunking strategies for large responses.
-
-[[group]]
-name = "download_sweep"
-bandwidth = 100
-protocol_latency = 25
-upload-size = 1024
-
-[[bench]]
-group = "download_sweep"
-download-size = 1024
-
-[[bench]]
-group = "download_sweep"
-download-size = 2048
-
-[[bench]]
-group = "download_sweep"
-download-size = 5120
-
-[[bench]]
-group = "download_sweep"
-download-size = 10240
-
-[[bench]]
-group = "download_sweep"
-download-size = 20480
-
-[[bench]]
-group = "download_sweep"
-download-size = 30720
-
-[[bench]]
-group = "download_sweep"
-download-size = 40960
-
-[[bench]]
-group = "download_sweep"
-download-size = 51200

crates/harness/bench_latency_sweep.toml

@@ -1,47 +0,0 @@
-#### Latency Sweep Benchmark ####
-#
-# Measures how network latency affects TLSNotary runtime.
-# Keeps bandwidth and payload sizes fixed while varying protocol latency.
-#
-# Fixed parameters:
-#   - Bandwidth: 100 Mbps (typical good connection)
-#   - Upload: 1KB (typical request)
-#   - Download: 2KB (typical response)
-#
-# Variable: Protocol latency from 10ms to 200ms
-#
-# Use this to plot "Latency vs Runtime" and understand latency sensitivity.
-
-[[group]]
-name = "latency_sweep"
-bandwidth = 100
-upload-size = 1024
-download-size = 2048
-
-[[bench]]
-group = "latency_sweep"
-protocol_latency = 10
-
-[[bench]]
-group = "latency_sweep"
-protocol_latency = 25
-
-[[bench]]
-group = "latency_sweep"
-protocol_latency = 50
-
-[[bench]]
-group = "latency_sweep"
-protocol_latency = 75
-
-[[bench]]
-group = "latency_sweep"
-protocol_latency = 100
-
-[[bench]]
-group = "latency_sweep"
-protocol_latency = 150
-
-[[bench]]
-group = "latency_sweep"
-protocol_latency = 200

crates/harness/plot/Cargo.toml

@@ -7,10 +7,9 @@ publish = false
 [dependencies]
 tlsn-harness-core = { workspace = true }
 # tlsn-server-fixture = { workspace = true }
-charming = { version = "0.5.1", features = ["ssr"] }
-csv = "1.3.0"
+charming = { version = "0.6.0", features = ["ssr"] }
 clap = { workspace = true, features = ["derive", "env"] }
-itertools = "0.14.0"
+polars = { version = "0.44", features = ["csv", "lazy"] }
 toml = { workspace = true }
 
 

crates/harness/plot/README.md

@@ -0,0 +1,111 @@
+# TLSNotary Benchmark Plot Tool
+
+Generates interactive HTML and SVG plots from TLSNotary benchmark results. Supports comparing multiple benchmark runs (e.g., before/after optimization, native vs browser).
+
+## Usage
+
+```bash
+tlsn-harness-plot <TOML> <CSV>... [OPTIONS]
+```
+
+### Arguments
+
+- `<TOML>` - Path to Bench.toml file defining benchmark structure
+- `<CSV>...` - One or more CSV files with benchmark results
+
+### Options
+
+- `-l, --labels <LABEL>...` - Labels for each dataset (optional)
+  - If omitted, datasets are labeled "Dataset 1", "Dataset 2", etc.
+  - Number of labels must match number of CSV files
+- `--min-max-band` - Add min/max bands to plots showing variance
+- `-h, --help` - Print help information
+
+## Examples
+
+### Single Dataset
+
+```bash
+tlsn-harness-plot bench.toml results.csv
+```
+
+Generates plots from a single benchmark run.
+
+### Compare Two Runs
+
+```bash
+tlsn-harness-plot bench.toml before.csv after.csv \
+  --labels "Before Optimization" "After Optimization"
+```
+
+Overlays two datasets to compare performance improvements.
+
+### Multiple Datasets
+
+```bash
+tlsn-harness-plot bench.toml native.csv browser.csv wasm.csv \
+  --labels "Native" "Browser" "WASM"
+```
+
+Compare three different runtime environments.
+
+### With Min/Max Bands
+
+```bash
+tlsn-harness-plot bench.toml run1.csv run2.csv \
+  --labels "Config A" "Config B" \
+  --min-max-band
+```
+
+Shows variance ranges for each dataset.
+
+## Output Files
+
+The tool generates two files per benchmark group:
+
+- `<output>.html` - Interactive HTML chart (zoomable, hoverable)
+- `<output>.svg` - Static SVG image for documentation
+
+Default output filenames:
+- `runtime_vs_bandwidth.{html,svg}` - When `protocol_latency` is defined in group
+- `runtime_vs_latency.{html,svg}` - When `bandwidth` is defined in group
+
+## Plot Format
+
+Each dataset displays:
+- **Solid line** - Total runtime (preprocessing + online phase)
+- **Dashed line** - Online phase only
+- **Shaded area** (optional) - Min/max variance bands
+
+Different datasets automatically use distinct colors for easy comparison.
+
+## CSV Format
+
+Expected columns in each CSV file:
+- `group` - Benchmark group name (must match TOML)
+- `bandwidth` - Network bandwidth in Kbps (for bandwidth plots)
+- `latency` - Network latency in ms (for latency plots)
+- `time_preprocess` - Preprocessing time in ms
+- `time_online` - Online phase time in ms
+- `time_total` - Total runtime in ms
+
+## TOML Format
+
+The benchmark TOML file defines groups with either:
+
+```toml
+[[group]]
+name = "my_benchmark"
+protocol_latency = 50  # Fixed latency for bandwidth plots
+# OR
+bandwidth = 10000      # Fixed bandwidth for latency plots
+```
+
+All datasets must use the same TOML file to ensure consistent benchmark structure.
+
+## Tips
+
+- Use descriptive labels to make plots self-documenting
+- Keep CSV files from the same benchmark configuration for valid comparisons
+- Min/max bands are useful for showing stability but can clutter plots with many datasets
+- Interactive HTML plots support zooming and hovering for detailed values

crates/harness/plot/bin/plot.rs

@@ -1,17 +1,18 @@
 use std::f32;
 
 use charming::{
-    Chart, HtmlRenderer,
+    Chart, HtmlRenderer, ImageRenderer,
     component::{Axis, Legend, Title},
-    element::{AreaStyle, LineStyle, NameLocation, Orient, TextStyle, Tooltip, Trigger},
+    element::{
+        AreaStyle, ItemStyle, LineStyle, LineStyleType, NameLocation, Orient, TextStyle, Tooltip,
+        Trigger,
+    },
     series::Line,
     theme::Theme,
 };
 use clap::Parser;
-use harness_core::bench::{BenchItems, Measurement};
-use itertools::Itertools;
-
-const THEME: Theme = Theme::Default;
+use harness_core::bench::BenchItems;
+use polars::prelude::*;
 
 #[derive(Parser, Debug)]
 #[command(author, version, about)]
@@ -19,72 +20,131 @@ struct Cli {
     /// Path to the Bench.toml file with benchmark spec
     toml: String,
 
-    /// Path to the CSV file with benchmark results
-    csv: String,
+    /// Paths to CSV files with benchmark results (one or more)
+    csv: Vec<String>,
 
-    /// Prover kind: native or browser
-    #[arg(short, long, value_enum, default_value = "native")]
-    prover_kind: ProverKind,
+    /// Labels for each dataset (optional, defaults to "Dataset 1", "Dataset 2", etc.)
+    #[arg(short, long, num_args = 0..)]
+    labels: Vec<String>,
 
     /// Add min/max bands to plots
     #[arg(long, default_value_t = false)]
     min_max_band: bool,
 }
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq, clap::ValueEnum)]
-enum ProverKind {
-    Native,
-    Browser,
-}
-
-impl std::fmt::Display for ProverKind {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        match self {
-            ProverKind::Native => write!(f, "Native"),
-            ProverKind::Browser => write!(f, "Browser"),
-        }
-    }
-}
-
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let cli = Cli::parse();
 
-    let mut rdr = csv::Reader::from_path(&cli.csv)?;
+    if cli.csv.is_empty() {
+        return Err("At least one CSV file must be provided".into());
+    }
+
+    // Generate labels if not provided
+    let labels: Vec<String> = if cli.labels.is_empty() {
+        cli.csv
+            .iter()
+            .enumerate()
+            .map(|(i, _)| format!("Dataset {}", i + 1))
+            .collect()
+    } else if cli.labels.len() != cli.csv.len() {
+        return Err(format!(
+            "Number of labels ({}) must match number of CSV files ({})",
+            cli.labels.len(),
+            cli.csv.len()
+        )
+        .into());
+    } else {
+        cli.labels.clone()
+    };
+
+    // Load all CSVs and add dataset label
+    let mut dfs = Vec::new();
+    for (csv_path, label) in cli.csv.iter().zip(labels.iter()) {
+        let mut df = CsvReadOptions::default()
+            .try_into_reader_with_file_path(Some(csv_path.clone().into()))?
+            .finish()?;
+
+        let label_series = Series::new("dataset_label".into(), vec![label.as_str(); df.height()]);
+        df.with_column(label_series)?;
+        dfs.push(df);
+    }
+
+    // Combine all dataframes
+    let df = dfs
+        .into_iter()
+        .reduce(|acc, df| acc.vstack(&df).unwrap())
+        .unwrap();
 
     let items: BenchItems = toml::from_str(&std::fs::read_to_string(&cli.toml)?)?;
     let groups = items.group;
 
-    // Prepare data for plotting.
-    let all_data: Vec<Measurement> = rdr
-        .deserialize::<Measurement>()
-        .collect::<Result<Vec<_>, _>>()?;
-
     for group in groups {
-        if group.protocol_latency.is_some() {
-            let latency = group.protocol_latency.unwrap();
-            plot_runtime_vs(
-                &all_data,
-                cli.min_max_band,
-                &group.name,
-                |r| r.bandwidth as f32 / 1000.0, // Kbps to Mbps
-                "Runtime vs Bandwidth",
-                format!("{} ms Latency, {} mode", latency, cli.prover_kind),
-                "runtime_vs_bandwidth.html",
-                "Bandwidth (Mbps)",
-            )?;
+        // Determine which field varies in benches for this group
+        let benches_in_group: Vec<_> = items
+            .bench
+            .iter()
+            .filter(|b| b.group.as_deref() == Some(&group.name))
+            .collect();
+
+        if benches_in_group.is_empty() {
+            continue;
         }
 
-        if group.bandwidth.is_some() {
-            let bandwidth = group.bandwidth.unwrap();
+        // Check which field has varying values
+        let bandwidth_varies = benches_in_group
+            .windows(2)
+            .any(|w| w[0].bandwidth != w[1].bandwidth);
+        let latency_varies = benches_in_group
+            .windows(2)
+            .any(|w| w[0].protocol_latency != w[1].protocol_latency);
+        let download_size_varies = benches_in_group
+            .windows(2)
+            .any(|w| w[0].download_size != w[1].download_size);
+
+        if download_size_varies {
+            let upload_size = group.upload_size.unwrap_or(1024);
             plot_runtime_vs(
-                &all_data,
+                &df,
+                &labels,
                 cli.min_max_band,
                 &group.name,
-                |r| r.latency as f32,
+                "download_size",
+                1.0 / 1024.0, // bytes to KB
+                "Runtime vs Response Size",
+                format!("{} bytes upload size", upload_size),
+                "runtime_vs_download_size",
+                "Response Size (KB)",
+                true, // legend on left
+            )?;
+        } else if bandwidth_varies {
+            let latency = group.protocol_latency.unwrap_or(50);
+            plot_runtime_vs(
+                &df,
+                &labels,
+                cli.min_max_band,
+                &group.name,
+                "bandwidth",
+                1.0 / 1000.0, // Kbps to Mbps
+                "Runtime vs Bandwidth",
+                format!("{} ms Latency", latency),
+                "runtime_vs_bandwidth",
+                "Bandwidth (Mbps)",
+                false, // legend on right
+            )?;
+        } else if latency_varies {
+            let bandwidth = group.bandwidth.unwrap_or(1000);
+            plot_runtime_vs(
+                &df,
+                &labels,
+                cli.min_max_band,
+                &group.name,
+                "latency",
+                1.0,
                 "Runtime vs Latency",
-                format!("{} bps bandwidth, {} mode", bandwidth, cli.prover_kind),
-                "runtime_vs_latency.html",
+                format!("{} bps bandwidth", bandwidth),
+                "runtime_vs_latency",
                 "Latency (ms)",
+                true, // legend on left
             )?;
         }
     }
@@ -92,83 +152,51 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     Ok(())
 }
 
-struct DataPoint {
-    min: f32,
-    mean: f32,
-    max: f32,
-}
-
-struct Points {
-    preprocess: DataPoint,
-    online: DataPoint,
-    total: DataPoint,
-}
-
 #[allow(clippy::too_many_arguments)]
-fn plot_runtime_vs<Fx>(
-    all_data: &[Measurement],
+fn plot_runtime_vs(
+    df: &DataFrame,
+    labels: &[String],
     show_min_max: bool,
     group: &str,
-    x_value: Fx,
+    x_col: &str,
+    x_scale: f32,
     title: &str,
     subtitle: String,
     output_file: &str,
     x_axis_label: &str,
-) -> Result<Chart, Box<dyn std::error::Error>>
-where
-    Fx: Fn(&Measurement) -> f32,
-{
-    fn data_point(values: &[f32]) -> DataPoint {
-        let mean = values.iter().copied().sum::<f32>() / values.len() as f32;
-        let max = values.iter().copied().reduce(f32::max).unwrap_or_default();
-        let min = values.iter().copied().reduce(f32::min).unwrap_or_default();
-        DataPoint { min, mean, max }
-    }
+    legend_left: bool,
+) -> Result<Chart, Box<dyn std::error::Error>> {
+    let stats_df = df
+        .clone()
+        .lazy()
+        .filter(col("group").eq(lit(group)))
+        .with_column((col(x_col).cast(DataType::Float32) * lit(x_scale)).alias("x"))
+        .with_columns([
+            (col("time_preprocess").cast(DataType::Float32) / lit(1000.0)).alias("preprocess"),
+            (col("time_online").cast(DataType::Float32) / lit(1000.0)).alias("online"),
+            (col("time_total").cast(DataType::Float32) / lit(1000.0)).alias("total"),
+        ])
+        .group_by([col("x"), col("dataset_label")])
+        .agg([
+            col("preprocess").min().alias("preprocess_min"),
+            col("preprocess").mean().alias("preprocess_mean"),
+            col("preprocess").max().alias("preprocess_max"),
+            col("online").min().alias("online_min"),
+            col("online").mean().alias("online_mean"),
+            col("online").max().alias("online_max"),
+            col("total").min().alias("total_min"),
+            col("total").mean().alias("total_mean"),
+            col("total").max().alias("total_max"),
+        ])
+        .sort(["dataset_label", "x"], Default::default())
+        .collect()?;
 
-    let stats: Vec<(f32, Points)> = all_data
-        .iter()
-        .filter(|r| r.group.as_deref() == Some(group))
-        .map(|r| {
-            (
-                x_value(r),
-                r.time_preprocess as f32 / 1000.0, // ms to s
-                r.time_online as f32 / 1000.0,
-                r.time_total as f32 / 1000.0,
-            )
-        })
-        .sorted_by(|a, b| a.0.partial_cmp(&b.0).unwrap())
-        .chunk_by(|entry| entry.0)
-        .into_iter()
-        .map(|(x, group)| {
-            let group_vec: Vec<_> = group.collect();
-            let preprocess = data_point(
-                &group_vec
-                    .iter()
-                    .map(|(_, t, _, _)| *t)
-                    .collect::<Vec<f32>>(),
-            );
-            let online = data_point(
-                &group_vec
-                    .iter()
-                    .map(|(_, _, t, _)| *t)
-                    .collect::<Vec<f32>>(),
-            );
-            let total = data_point(
-                &group_vec
-                    .iter()
-                    .map(|(_, _, _, t)| *t)
-                    .collect::<Vec<f32>>(),
-            );
-            (
-                x,
-                Points {
-                    preprocess,
-                    online,
-                    total,
-                },
-            )
-        })
-        .collect();
+    // Build legend entries
+    let mut legend_data = Vec::new();
+    for label in labels {
+        legend_data.push(format!("Total Mean ({})", label));
+        legend_data.push(format!("Online Mean ({})", label));
+    }
 
     let mut chart = Chart::new()
         .title(
@@ -179,14 +207,6 @@ where
                 .subtext_style(TextStyle::new().font_size(16)),
         )
         .tooltip(Tooltip::new().trigger(Trigger::Axis))
-        .legend(
-            Legend::new()
-                .data(vec!["Preprocess Mean", "Online Mean", "Total Mean"])
-                .top("80")
-                .right("110")
-                .orient(Orient::Vertical)
-                .item_gap(10),
-        )
         .x_axis(
             Axis::new()
                 .name(x_axis_label)
@@ -205,73 +225,156 @@ where
                 .name_text_style(TextStyle::new().font_size(21)),
         );
 
-    chart = add_mean_series(chart, &stats, "Preprocess Mean", |p| p.preprocess.mean);
-    chart = add_mean_series(chart, &stats, "Online Mean", |p| p.online.mean);
-    chart = add_mean_series(chart, &stats, "Total Mean", |p| p.total.mean);
+    // Add legend with conditional positioning
+    let legend = Legend::new()
+        .data(legend_data)
+        .top("80")
+        .orient(Orient::Vertical)
+        .item_gap(10);
 
-    if show_min_max {
-        chart = add_min_max_band(
-            chart,
-            &stats,
-            "Preprocess Min/Max",
-            |p| &p.preprocess,
-            "#ccc",
-        );
-        chart = add_min_max_band(chart, &stats, "Online Min/Max", |p| &p.online, "#ccc");
-        chart = add_min_max_band(chart, &stats, "Total Min/Max", |p| &p.total, "#ccc");
+    let legend = if legend_left {
+        legend.left("110")
+    } else {
+        legend.right("110")
+    };
+
+    chart = chart.legend(legend);
+
+    // Define colors for each dataset
+    let colors = vec![
+        "#5470c6", "#91cc75", "#fac858", "#ee6666", "#73c0de", "#3ba272", "#fc8452", "#9a60b4",
+    ];
+
+    for (idx, label) in labels.iter().enumerate() {
+        let color = colors.get(idx % colors.len()).unwrap();
+
+        // Total time - solid line
+        chart = add_dataset_series(
+            &chart,
+            &stats_df,
+            label,
+            &format!("Total Mean ({})", label),
+            "total_mean",
+            false,
+            color,
+        )?;
+
+        // Online time - dashed line (same color as total)
+        chart = add_dataset_series(
+            &chart,
+            &stats_df,
+            label,
+            &format!("Online Mean ({})", label),
+            "online_mean",
+            true,
+            color,
+        )?;
+
+        if show_min_max {
+            chart = add_dataset_min_max_band(
+                &chart,
+                &stats_df,
+                label,
+                &format!("Total Min/Max ({})", label),
+                "total",
+                color,
+            )?;
+        }
     }
-    // Save the chart as HTML file.
+    // Save the chart as HTML file (no theme)
     HtmlRenderer::new(title, 1000, 800)
-        .theme(THEME)
-        .save(&chart, output_file)
+        .save(&chart, &format!("{}.html", output_file))
+        .unwrap();
+
+    // Save SVG with default theme
+    ImageRenderer::new(1000, 800)
+        .theme(Theme::Default)
+        .save(&chart, &format!("{}.svg", output_file))
+        .unwrap();
+
+    // Save SVG with dark theme
+    ImageRenderer::new(1000, 800)
+        .theme(Theme::Dark)
+        .save(&chart, &format!("{}_dark.svg", output_file))
         .unwrap();
 
     Ok(chart)
 }
 
-fn add_mean_series(
-    chart: Chart,
-    stats: &[(f32, Points)],
-    name: &str,
-    extract: impl Fn(&Points) -> f32,
-) -> Chart {
-    chart.series(
-        Line::new()
-            .name(name)
-            .data(
-                stats
-                    .iter()
-                    .map(|(x, points)| vec![*x, extract(points)])
-                    .collect(),
-            )
-            .symbol_size(6),
-    )
+fn add_dataset_series(
+    chart: &Chart,
+    df: &DataFrame,
+    dataset_label: &str,
+    series_name: &str,
+    col_name: &str,
+    dashed: bool,
+    color: &str,
+) -> Result<Chart, Box<dyn std::error::Error>> {
+    // Filter for specific dataset
+    let mask = df.column("dataset_label")?.str()?.equal(dataset_label);
+    let filtered = df.filter(&mask)?;
+
+    let x = filtered.column("x")?.f32()?;
+    let y = filtered.column(col_name)?.f32()?;
+
+    let data: Vec<Vec<f32>> = x
+        .into_iter()
+        .zip(y.into_iter())
+        .filter_map(|(x, y)| Some(vec![x?, y?]))
+        .collect();
+
+    let mut line = Line::new()
+        .name(series_name)
+        .data(data)
+        .symbol_size(6)
+        .item_style(ItemStyle::new().color(color));
+
+    let mut line_style = LineStyle::new();
+    if dashed {
+        line_style = line_style.type_(LineStyleType::Dashed);
+    }
+    line = line.line_style(line_style.color(color));
+
+    Ok(chart.clone().series(line))
 }
 
-fn add_min_max_band(
-    chart: Chart,
-    stats: &[(f32, Points)],
+fn add_dataset_min_max_band(
+    chart: &Chart,
+    df: &DataFrame,
+    dataset_label: &str,
     name: &str,
-    extract: impl Fn(&Points) -> &DataPoint,
+    col_prefix: &str,
     color: &str,
-) -> Chart {
-    chart.series(
+) -> Result<Chart, Box<dyn std::error::Error>> {
+    // Filter for specific dataset
+    let mask = df.column("dataset_label")?.str()?.equal(dataset_label);
+    let filtered = df.filter(&mask)?;
+
+    let x = filtered.column("x")?.f32()?;
+    let min_col = filtered.column(&format!("{}_min", col_prefix))?.f32()?;
+    let max_col = filtered.column(&format!("{}_max", col_prefix))?.f32()?;
+
+    let max_data: Vec<Vec<f32>> = x
+        .into_iter()
+        .zip(max_col.into_iter())
+        .filter_map(|(x, y)| Some(vec![x?, y?]))
+        .collect();
+
+    let min_data: Vec<Vec<f32>> = x
+        .into_iter()
+        .zip(min_col.into_iter())
+        .filter_map(|(x, y)| Some(vec![x?, y?]))
+        .rev()
+        .collect();
+
+    let data: Vec<Vec<f32>> = max_data.into_iter().chain(min_data).collect();
+
+    Ok(chart.clone().series(
         Line::new()
             .name(name)
-            .data(
-                stats
-                    .iter()
-                    .map(|(x, points)| vec![*x, extract(points).max])
-                    .chain(
-                        stats
-                            .iter()
-                            .rev()
-                            .map(|(x, points)| vec![*x, extract(points).min]),
-                    )
-                    .collect(),
-            )
+            .data(data)
             .show_symbol(false)
             .line_style(LineStyle::new().opacity(0.0))
             .area_style(AreaStyle::new().opacity(0.3).color(color)),
-    )
+    ))
 }

crates/harness/runner/Cargo.toml

@@ -22,7 +22,6 @@ clap = { workspace = true, features = ["derive", "env"] }
 csv = { version = "1.3" }
 duct = { version = "1" }
 futures = { workspace = true }
-indicatif = { version = "0.17" }
 ipnet = { workspace = true }
 serio = { workspace = true }
 serde_json = { workspace = true }

crates/harness/runner/src/cli.rs

@@ -16,10 +16,6 @@ pub struct Cli {
     /// Subnet to assign harness network interfaces.
     #[arg(long, default_value = "10.250.0.0/24", env = "SUBNET")]
     pub subnet: Ipv4Net,
-    /// Run browser in headed mode (visible window) for debugging.
-    /// Works with both X11 and Wayland.
-    #[arg(long)]
-    pub headed: bool,
 }
 
 #[derive(Subcommand)]
@@ -35,13 +31,10 @@ pub enum Command {
     },
     /// runs benchmarks.
     Bench {
-        /// Configuration path. Defaults to bench.toml which contains
-        /// representative scenarios (cable, 5G, fiber) for quick performance
-        /// checks. Use bench_*_sweep.toml files for parametric
-        /// analysis.
+        /// Configuration path.
         #[arg(short, long, default_value = "bench.toml")]
         config: PathBuf,
-        /// Output CSV file path for detailed metrics and post-processing.
+        /// Output file path.
         #[arg(short, long, default_value = "metrics.csv")]
         output: PathBuf,
         /// Number of samples to measure per benchmark. This is overridden by

crates/harness/runner/src/executor.rs

@@ -28,9 +28,6 @@ pub struct Executor {
     ns: Namespace,
     config: ExecutorConfig,
     target: Target,
-    /// Display environment variables for headed mode (X11/Wayland).
-    /// Empty means headless mode.
-    display_env: Vec<String>,
     state: State,
 }
 
@@ -52,17 +49,11 @@ impl State {
 }
 
 impl Executor {
-    pub fn new(
-        ns: Namespace,
-        config: ExecutorConfig,
-        target: Target,
-        display_env: Vec<String>,
-    ) -> Self {
+    pub fn new(ns: Namespace, config: ExecutorConfig, target: Target) -> Self {
         Self {
             ns,
             config,
             target,
-            display_env,
             state: State::Init,
         }
     }
@@ -129,49 +120,23 @@ impl Executor {
                 let tmp = duct::cmd!("mktemp", "-d").read()?;
                 let tmp = tmp.trim();
 
-                let headed = !self.display_env.is_empty();
-
-                // Build command args based on headed/headless mode
-                let mut args: Vec<String> = vec![
-                    "ip".into(),
-                    "netns".into(),
-                    "exec".into(),
-                    self.ns.name().into(),
-                ];
-
-                if headed {
-                    // For headed mode: drop back to the current user and pass display env vars
-                    // This allows the browser to connect to X11/Wayland while in the namespace
-                    let user =
-                        std::env::var("USER").context("USER environment variable not set")?;
-                    args.extend(["sudo".into(), "-E".into(), "-u".into(), user, "env".into()]);
-                    args.extend(self.display_env.clone());
-                }
-
-                args.push(chrome_path.to_string_lossy().into());
-                args.push(format!("--remote-debugging-port={PORT_BROWSER}"));
-
-                if headed {
-                    // Headed mode: no headless, add flags to suppress first-run dialogs
-                    args.extend(["--no-first-run".into(), "--no-default-browser-check".into()]);
-                } else {
-                    // Headless mode: original flags
-                    args.extend([
-                        "--headless".into(),
-                        "--disable-dev-shm-usage".into(),
-                        "--disable-gpu".into(),
-                        "--disable-cache".into(),
-                        "--disable-application-cache".into(),
-                    ]);
-                }
-
-                args.extend([
-                    "--no-sandbox".into(),
+                let process = duct::cmd!(
+                    "sudo",
+                    "ip",
+                    "netns",
+                    "exec",
+                    self.ns.name(),
+                    chrome_path,
+                    format!("--remote-debugging-port={PORT_BROWSER}"),
+                    "--headless",
+                    "--disable-dev-shm-usage",
+                    "--disable-gpu",
+                    "--disable-cache",
+                    "--disable-application-cache",
+                    "--no-sandbox",
                     format!("--user-data-dir={tmp}"),
-                    "--allowed-ips=10.250.0.1".into(),
-                ]);
-
-                let process = duct::cmd("sudo", &args);
+                    format!("--allowed-ips=10.250.0.1"),
+                );
 
                 let process = if !cfg!(feature = "debug") {
                     process.stderr_capture().stdout_capture().start()?

crates/harness/runner/src/lib.rs

@@ -9,7 +9,7 @@ mod ws_proxy;
 #[cfg(feature = "debug")]
 mod debug_prelude;
 
-use std::{collections::HashMap, time::Duration};
+use std::time::Duration;
 
 use anyhow::Result;
 use clap::Parser;
@@ -22,7 +22,6 @@ use harness_core::{
     rpc::{BenchCmd, TestCmd},
     test::TestStatus,
 };
-use indicatif::{ProgressBar, ProgressStyle};
 
 use cli::{Cli, Command};
 use executor::Executor;
@@ -33,60 +32,6 @@ use crate::debug_prelude::*;
 
 use crate::{cli::Route, network::Network, wasm_server::WasmServer, ws_proxy::WsProxy};
 
-/// Statistics for a benchmark configuration
-#[derive(Debug, Clone)]
-struct BenchStats {
-    group: Option<String>,
-    bandwidth: usize,
-    latency: usize,
-    upload_size: usize,
-    download_size: usize,
-    times: Vec<u64>,
-}
-
-impl BenchStats {
-    fn median(&self) -> f64 {
-        let mut sorted = self.times.clone();
-        sorted.sort();
-        let len = sorted.len();
-        if len == 0 {
-            return 0.0;
-        }
-        if len.is_multiple_of(2) {
-            (sorted[len / 2 - 1] + sorted[len / 2]) as f64 / 2.0
-        } else {
-            sorted[len / 2] as f64
-        }
-    }
-}
-
-/// Print summary table of benchmark results
-fn print_bench_summary(stats: &[BenchStats]) {
-    if stats.is_empty() {
-        println!("\nNo benchmark results to display (only warmup was run).");
-        return;
-    }
-
-    println!("\n{}", "=".repeat(80));
-    println!("TLSNotary Benchmark Results");
-    println!("{}", "=".repeat(80));
-    println!();
-
-    for stat in stats {
-        let group_name = stat.group.as_deref().unwrap_or("unnamed");
-        println!(
-            "{} ({} Mbps, {}ms latency, {}KB↑ {}KB↓):",
-            group_name,
-            stat.bandwidth,
-            stat.latency,
-            stat.upload_size / 1024,
-            stat.download_size / 1024
-        );
-        println!("  Median:  {:.2}s", stat.median() / 1000.0);
-        println!();
-    }
-}
-
 #[derive(Debug, Clone, Copy, PartialEq, Eq, clap::ValueEnum, Default)]
 pub enum Target {
     #[default]
@@ -105,46 +50,14 @@ struct Runner {
     started: bool,
 }
 
-/// Collects display-related environment variables for headed browser mode.
-/// Works with both X11 and Wayland by collecting whichever vars are present.
-fn collect_display_env_vars() -> Vec<String> {
-    const DISPLAY_VARS: &[&str] = &[
-        "DISPLAY",         // X11
-        "XAUTHORITY",      // X11 auth
-        "WAYLAND_DISPLAY", // Wayland
-        "XDG_RUNTIME_DIR", // Wayland runtime dir
-    ];
-
-    DISPLAY_VARS
-        .iter()
-        .filter_map(|&var| {
-            std::env::var(var)
-                .ok()
-                .map(|val| format!("{}={}", var, val))
-        })
-        .collect()
-}
-
 impl Runner {
     fn new(cli: &Cli) -> Result<Self> {
-        let Cli {
-            target,
-            subnet,
-            headed,
-            ..
-        } = cli;
+        let Cli { target, subnet, .. } = cli;
         let current_path = std::env::current_exe().unwrap();
         let fixture_path = current_path.parent().unwrap().join("server-fixture");
         let network_config = NetworkConfig::new(*subnet);
         let network = Network::new(network_config.clone())?;
 
-        // Collect display env vars once if headed mode is enabled
-        let display_env = if *headed {
-            collect_display_env_vars()
-        } else {
-            Vec::new()
-        };
-
         let server_fixture =
             ServerFixture::new(fixture_path, network.ns_app().clone(), network_config.app);
         let wasm_server = WasmServer::new(
@@ -162,7 +75,6 @@ impl Runner {
                 .network_config(network_config.clone())
                 .build(),
             *target,
-            display_env.clone(),
         );
         let exec_v = Executor::new(
             network.ns_1().clone(),
@@ -172,7 +84,6 @@ impl Runner {
                 .network_config(network_config.clone())
                 .build(),
             Target::Native,
-            Vec::new(), // Verifier doesn't need display env
         );
 
         Ok(Self {
@@ -207,12 +118,6 @@ pub async fn main() -> Result<()> {
     tracing_subscriber::fmt::init();
 
     let cli = Cli::parse();
-
-    // Validate --headed requires --target browser
-    if cli.headed && cli.target != Target::Browser {
-        anyhow::bail!("--headed can only be used with --target browser");
-    }
-
     let mut runner = Runner::new(&cli)?;
 
     let mut exit_code = 0;
@@ -301,12 +206,6 @@ pub async fn main() -> Result<()> {
             samples_override,
             skip_warmup,
         } => {
-            // Print configuration info
-            println!("TLSNotary Benchmark Harness");
-            println!("Running benchmarks from: {}", config.display());
-            println!("Output will be written to: {}", output.display());
-            println!();
-
             let items: BenchItems = toml::from_str(&std::fs::read_to_string(config)?)?;
             let output_file = std::fs::File::create(output)?;
             let mut writer = WriterBuilder::new().from_writer(output_file);
@@ -321,34 +220,7 @@ pub async fn main() -> Result<()> {
             runner.exec_p.start().await?;
             runner.exec_v.start().await?;
 
-            // Create progress bar
-            let pb = ProgressBar::new(benches.len() as u64);
-            pb.set_style(
-                ProgressStyle::default_bar()
-                    .template("[{elapsed_precise}] {bar:40.cyan/blue} {pos}/{len} {msg}")
-                    .expect("valid template")
-                    .progress_chars("█▓▒░ "),
-            );
-
-            // Collect measurements for stats
-            let mut measurements_by_config: HashMap<String, Vec<u64>> = HashMap::new();
-
-            let warmup_count = if skip_warmup { 0 } else { 3 };
-
-            for (idx, config) in benches.iter().enumerate() {
-                let is_warmup = idx < warmup_count;
-
-                let group_name = if is_warmup {
-                    format!("Warmup {}/{}", idx + 1, warmup_count)
-                } else {
-                    config.group.as_deref().unwrap_or("unnamed").to_string()
-                };
-
-                pb.set_message(format!(
-                    "{} ({} Mbps, {}ms)",
-                    group_name, config.bandwidth, config.protocol_latency
-                ));
-
+            for config in benches {
                 runner
                     .network
                     .set_proto_config(config.bandwidth, config.protocol_latency.div_ceil(2))?;
@@ -377,73 +249,11 @@ pub async fn main() -> Result<()> {
                     panic!("expected prover output");
                 };
 
-                // Collect metrics for stats (skip warmup benches)
-                if !is_warmup {
-                    let config_key = format!(
-                        "{:?}|{}|{}|{}|{}",
-                        config.group,
-                        config.bandwidth,
-                        config.protocol_latency,
-                        config.upload_size,
-                        config.download_size
-                    );
-                    measurements_by_config
-                        .entry(config_key)
-                        .or_default()
-                        .push(metrics.time_total);
-                }
-
-                let measurement = Measurement::new(config.clone(), metrics);
+                let measurement = Measurement::new(config, metrics);
 
                 writer.serialize(measurement)?;
                 writer.flush()?;
-
-                pb.inc(1);
             }
-
-            pb.finish_with_message("Benchmarks complete");
-
-            // Compute and print statistics
-            let mut all_stats: Vec<BenchStats> = Vec::new();
-            for (key, times) in measurements_by_config {
-                // Parse back the config from the key
-                let parts: Vec<&str> = key.split('|').collect();
-                if parts.len() >= 5 {
-                    let group = if parts[0] == "None" {
-                        None
-                    } else {
-                        Some(
-                            parts[0]
-                                .trim_start_matches("Some(\"")
-                                .trim_end_matches("\")")
-                                .to_string(),
-                        )
-                    };
-                    let bandwidth: usize = parts[1].parse().unwrap_or(0);
-                    let latency: usize = parts[2].parse().unwrap_or(0);
-                    let upload_size: usize = parts[3].parse().unwrap_or(0);
-                    let download_size: usize = parts[4].parse().unwrap_or(0);
-
-                    all_stats.push(BenchStats {
-                        group,
-                        bandwidth,
-                        latency,
-                        upload_size,
-                        download_size,
-                        times,
-                    });
-                }
-            }
-
-            // Sort stats by group name for consistent output
-            all_stats.sort_by(|a, b| {
-                a.group
-                    .cmp(&b.group)
-                    .then(a.latency.cmp(&b.latency))
-                    .then(a.bandwidth.cmp(&b.bandwidth))
-            });
-
-            print_bench_summary(&all_stats);
         }
         Command::Serve {} => {
             runner.start_services().await?;

crates/harness/toml/bandwidth.toml

@@ -0,0 +1,25 @@
+#### Bandwidth ####
+
+[[group]]
+name = "bandwidth"
+protocol_latency = 25
+
+[[bench]]
+group = "bandwidth"
+bandwidth = 10
+
+[[bench]]
+group = "bandwidth"
+bandwidth = 50
+
+[[bench]]
+group = "bandwidth"
+bandwidth = 100
+
+[[bench]]
+group = "bandwidth"
+bandwidth = 250
+
+[[bench]]
+group = "bandwidth"
+bandwidth = 1000

crates/harness/toml/download.toml

@@ -0,0 +1,37 @@
+[[group]]
+name = "download_size"
+protocol_latency = 10
+bandwidth = 200
+upload-size = 2048
+
+[[bench]]
+group = "download_size"
+download-size = 1024
+
+[[bench]]
+group = "download_size"
+download-size = 2048
+
+[[bench]]
+group = "download_size"
+download-size = 4096
+
+[[bench]]
+group = "download_size"
+download-size = 8192
+
+[[bench]]
+group = "download_size"
+download-size = 16384
+
+[[bench]]
+group = "download_size"
+download-size = 32768
+
+[[bench]]
+group = "download_size"
+download-size = 65536
+
+[[bench]]
+group = "download_size"
+download-size = 131072

crates/harness/toml/latency.toml

@@ -0,0 +1,25 @@
+#### Latency ####
+
+[[group]]
+name = "latency"
+bandwidth = 1000
+
+[[bench]]
+group = "latency"
+protocol_latency = 10
+
+[[bench]]
+group = "latency"
+protocol_latency = 25
+
+[[bench]]
+group = "latency"
+protocol_latency = 50
+
+[[bench]]
+group = "latency"
+protocol_latency = 100
+
+[[bench]]
+group = "latency"
+protocol_latency = 200

crates/tlsn/src/map.rs

@@ -21,6 +21,20 @@ impl<T> RangeMap<T>
 where
     T: Item,
 {
+    pub(crate) fn new(map: Vec<(usize, T)>) -> Self {
+        let mut pos = 0;
+        for (idx, item) in &map {
+            assert!(
+                *idx >= pos,
+                "items must be sorted by index and non-overlapping"
+            );
+
+            pos = *idx + item.length();
+        }
+
+        Self { map }
+    }
+
     /// Returns `true` if the map is empty.
     pub(crate) fn is_empty(&self) -> bool {
         self.map.is_empty()
@@ -33,6 +47,11 @@ where
             .map(|(idx, item)| *idx..*idx + item.length())
     }
 
+    /// Returns the length of the map.
+    pub(crate) fn len(&self) -> usize {
+        self.map.iter().map(|(_, item)| item.length()).sum()
+    }
+
     pub(crate) fn iter(&self) -> impl Iterator<Item = (Range<usize>, &T)> {
         self.map
             .iter()

crates/tlsn/src/mpz.rs

@@ -6,6 +6,11 @@ use mpz_core::Block;
 #[cfg(not(tlsn_insecure))]
 use mpz_garble::protocol::semihonest::{Evaluator, Garbler};
 use mpz_garble_core::Delta;
+use mpz_memory_core::{
+    Vector,
+    binary::U8,
+    correlated::{Key, Mac},
+};
 #[cfg(not(tlsn_insecure))]
 use mpz_ot::cot::{DerandCOTReceiver, DerandCOTSender};
 use mpz_ot::{
@@ -19,6 +24,8 @@ use tlsn_core::config::tls_commit::mpc::{MpcTlsConfig, NetworkSetting};
 use tlsn_deap::Deap;
 use tokio::sync::Mutex;
 
+use crate::transcript_internal::commit::encoding::{KeyStore, MacStore};
+
 #[cfg(not(tlsn_insecure))]
 pub(crate) type ProverMpc =
     Garbler<DerandCOTSender<SharedRCOTSender<kos::Sender<co::Receiver>, Block>>>;
@@ -186,3 +193,41 @@ pub(crate) fn translate_keys<Mpc, Zk>(keys: &mut SessionKeys, vm: &Deap<Mpc, Zk>
         .translate(keys.server_write_mac_key)
         .expect("VM memory should be consistent");
 }
+
+impl<T> KeyStore for Verifier<T> {
+    fn delta(&self) -> &Delta {
+        self.delta()
+    }
+
+    fn get_keys(&self, data: Vector<U8>) -> Option<&[Key]> {
+        self.get_keys(data).ok()
+    }
+}
+
+impl<T> MacStore for Prover<T> {
+    fn get_macs(&self, data: Vector<U8>) -> Option<&[Mac]> {
+        self.get_macs(data).ok()
+    }
+}
+
+#[cfg(tlsn_insecure)]
+mod insecure {
+    use super::*;
+    use mpz_ideal_vm::IdealVm;
+
+    impl KeyStore for IdealVm {
+        fn delta(&self) -> &Delta {
+            unimplemented!("encodings not supported in insecure mode")
+        }
+
+        fn get_keys(&self, _data: Vector<U8>) -> Option<&[Key]> {
+            unimplemented!("encodings not supported in insecure mode")
+        }
+    }
+
+    impl MacStore for IdealVm {
+        fn get_macs(&self, _data: Vector<U8>) -> Option<&[Mac]> {
+            unimplemented!("encodings not supported in insecure mode")
+        }
+    }
+}

crates/tlsn/src/prover/error.rs

@@ -2,6 +2,8 @@ use std::{error::Error, fmt};
 
 use mpc_tls::MpcTlsError;
 
+use crate::transcript_internal::commit::encoding::EncodingError;
+
 /// Error for [`Prover`](crate::prover::Prover).
 #[derive(Debug, thiserror::Error)]
 pub struct ProverError {
@@ -107,3 +109,9 @@ impl From<MpcTlsError> for ProverError {
         Self::new(ErrorKind::Mpc, e)
     }
 }
+
+impl From<EncodingError> for ProverError {
+    fn from(e: EncodingError) -> Self {
+        Self::new(ErrorKind::Commit, e)
+    }
+}

crates/tlsn/src/prover/prove.rs

@@ -13,10 +13,17 @@ use tlsn_core::{
 
 use crate::{
     prover::ProverError,
-    transcript_internal::{TranscriptRefs, auth::prove_plaintext, commit::hash::prove_hash},
+    transcript_internal::{
+        TranscriptRefs,
+        auth::prove_plaintext,
+        commit::{
+            encoding::{self, MacStore},
+            hash::prove_hash,
+        },
+    },
 };
 
-pub(crate) async fn prove<T: Vm<Binary> + Send + Sync>(
+pub(crate) async fn prove<T: Vm<Binary> + MacStore + Send + Sync>(
     ctx: &mut Context,
     vm: &mut T,
     keys: &SessionKeys,
@@ -38,6 +45,13 @@ pub(crate) async fn prove<T: Vm<Binary> + Send + Sync>(
                 Direction::Sent => commit_sent.union_mut(idx),
                 Direction::Received => commit_recv.union_mut(idx),
             });
+
+        commit_config
+            .iter_encoding()
+            .for_each(|(direction, idx)| match direction {
+                Direction::Sent => commit_sent.union_mut(idx),
+                Direction::Received => commit_recv.union_mut(idx),
+            });
     }
 
     let transcript_refs = TranscriptRefs {
@@ -88,6 +102,45 @@ pub(crate) async fn prove<T: Vm<Binary> + Send + Sync>(
 
     vm.execute_all(ctx).await.map_err(ProverError::zk)?;
 
+    if let Some(commit_config) = config.transcript_commit()
+        && commit_config.has_encoding()
+    {
+        let mut sent_ranges = RangeSet::default();
+        let mut recv_ranges = RangeSet::default();
+        for (dir, idx) in commit_config.iter_encoding() {
+            match dir {
+                Direction::Sent => sent_ranges.union_mut(idx),
+                Direction::Received => recv_ranges.union_mut(idx),
+            }
+        }
+
+        let sent_map = transcript_refs
+            .sent
+            .index(&sent_ranges)
+            .expect("indices are valid");
+        let recv_map = transcript_refs
+            .recv
+            .index(&recv_ranges)
+            .expect("indices are valid");
+
+        let (commitment, tree) = encoding::receive(
+            ctx,
+            vm,
+            *commit_config.encoding_hash_alg(),
+            &sent_map,
+            &recv_map,
+            commit_config.iter_encoding(),
+        )
+        .await?;
+
+        output
+            .transcript_commitments
+            .push(TranscriptCommitment::Encoding(commitment));
+        output
+            .transcript_secrets
+            .push(TranscriptSecret::Encoding(tree));
+    }
+
     if let Some((hash_fut, hash_secrets)) = hash_commitments {
         let hash_commitments = hash_fut.try_recv().map_err(ProverError::commit)?;
         for (commitment, secret) in hash_commitments.into_iter().zip(hash_secrets) {

crates/tlsn/src/transcript_internal/commit.rs

@@ -1,3 +1,4 @@
 //! Plaintext commitment and proof of encryption.
 
+pub(crate) mod encoding;
 pub(crate) mod hash;

crates/tlsn/src/transcript_internal/commit/encoding.rs

@@ -0,0 +1,267 @@
+//! Encoding commitment protocol.
+
+use std::ops::Range;
+
+use mpz_common::Context;
+use mpz_memory_core::{
+    Vector,
+    binary::U8,
+    correlated::{Delta, Key, Mac},
+};
+use rand::Rng;
+use rangeset::set::RangeSet;
+use serde::{Deserialize, Serialize};
+use serio::{SinkExt, stream::IoStreamExt};
+use tlsn_core::{
+    hash::{Blake3, HashAlgId, HashAlgorithm, Keccak256, Sha256},
+    transcript::{
+        Direction,
+        encoding::{
+            Encoder, EncoderSecret, EncodingCommitment, EncodingProvider, EncodingProviderError,
+            EncodingTree, EncodingTreeError, new_encoder,
+        },
+    },
+};
+
+use crate::{
+    map::{Item, RangeMap},
+    transcript_internal::ReferenceMap,
+};
+
+/// Bytes of encoding, per byte.
+const ENCODING_SIZE: usize = 128;
+
+#[derive(Debug, Serialize, Deserialize)]
+struct Encodings {
+    sent: Vec<u8>,
+    recv: Vec<u8>,
+}
+
+/// Transfers encodings for the provided plaintext ranges.
+pub(crate) async fn transfer<K: KeyStore>(
+    ctx: &mut Context,
+    store: &K,
+    sent: &ReferenceMap,
+    recv: &ReferenceMap,
+) -> Result<(EncoderSecret, EncodingCommitment), EncodingError> {
+    let secret = EncoderSecret::new(rand::rng().random(), store.delta().as_block().to_bytes());
+    let encoder = new_encoder(&secret);
+
+    // Collects the encodings for the provided plaintext ranges.
+    fn collect_encodings(
+        encoder: &impl Encoder,
+        store: &impl KeyStore,
+        direction: Direction,
+        map: &ReferenceMap,
+    ) -> Vec<u8> {
+        let mut encodings = Vec::with_capacity(map.len() * ENCODING_SIZE);
+        for (range, chunk) in map.iter() {
+            let start = encodings.len();
+            encoder.encode_range(direction, range, &mut encodings);
+            let keys = store
+                .get_keys(*chunk)
+                .expect("keys are present for provided plaintext ranges");
+            encodings[start..]
+                .iter_mut()
+                .zip(keys.iter().flat_map(|key| key.as_block().as_bytes()))
+                .for_each(|(encoding, key)| {
+                    *encoding ^= *key;
+                });
+        }
+        encodings
+    }
+
+    let encodings = Encodings {
+        sent: collect_encodings(&encoder, store, Direction::Sent, sent),
+        recv: collect_encodings(&encoder, store, Direction::Received, recv),
+    };
+
+    let frame_limit = ctx
+        .io()
+        .limit()
+        .saturating_add(encodings.sent.len() + encodings.recv.len());
+    ctx.io_mut().with_limit(frame_limit).send(encodings).await?;
+
+    let root = ctx.io_mut().expect_next().await?;
+
+    Ok((secret, EncodingCommitment { root }))
+}
+
+/// Receives and commits to the encodings for the provided plaintext ranges.
+pub(crate) async fn receive<M: MacStore>(
+    ctx: &mut Context,
+    store: &M,
+    hash_alg: HashAlgId,
+    sent: &ReferenceMap,
+    recv: &ReferenceMap,
+    idxs: impl IntoIterator<Item = &(Direction, RangeSet<usize>)>,
+) -> Result<(EncodingCommitment, EncodingTree), EncodingError> {
+    let hasher: &(dyn HashAlgorithm + Send + Sync) = match hash_alg {
+        HashAlgId::SHA256 => &Sha256::default(),
+        HashAlgId::KECCAK256 => &Keccak256::default(),
+        HashAlgId::BLAKE3 => &Blake3::default(),
+        alg => {
+            return Err(ErrorRepr::UnsupportedHashAlgorithm(alg).into());
+        }
+    };
+
+    let (sent_len, recv_len) = (sent.len(), recv.len());
+    let frame_limit = ctx
+        .io()
+        .limit()
+        .saturating_add(ENCODING_SIZE * (sent_len + recv_len));
+    let encodings: Encodings = ctx.io_mut().with_limit(frame_limit).expect_next().await?;
+
+    if encodings.sent.len() != sent_len * ENCODING_SIZE {
+        return Err(ErrorRepr::IncorrectMacCount {
+            direction: Direction::Sent,
+            expected: sent_len,
+            got: encodings.sent.len() / ENCODING_SIZE,
+        }
+        .into());
+    }
+
+    if encodings.recv.len() != recv_len * ENCODING_SIZE {
+        return Err(ErrorRepr::IncorrectMacCount {
+            direction: Direction::Received,
+            expected: recv_len,
+            got: encodings.recv.len() / ENCODING_SIZE,
+        }
+        .into());
+    }
+
+    // Collects a map of plaintext ranges to their encodings.
+    fn collect_map(
+        store: &impl MacStore,
+        mut encodings: Vec<u8>,
+        map: &ReferenceMap,
+    ) -> RangeMap<EncodingSlice> {
+        let mut encoding_map = Vec::new();
+        let mut pos = 0;
+        for (range, chunk) in map.iter() {
+            let macs = store
+                .get_macs(*chunk)
+                .expect("MACs are present for provided plaintext ranges");
+            let encoding = &mut encodings[pos..pos + range.len() * ENCODING_SIZE];
+            encoding
+                .iter_mut()
+                .zip(macs.iter().flat_map(|mac| mac.as_bytes()))
+                .for_each(|(encoding, mac)| {
+                    *encoding ^= *mac;
+                });
+
+            encoding_map.push((range.start, EncodingSlice::from(&(*encoding))));
+            pos += range.len() * ENCODING_SIZE;
+        }
+        RangeMap::new(encoding_map)
+    }
+
+    let provider = Provider {
+        sent: collect_map(store, encodings.sent, sent),
+        recv: collect_map(store, encodings.recv, recv),
+    };
+
+    let tree = EncodingTree::new(hasher, idxs, &provider)?;
+    let root = tree.root();
+
+    ctx.io_mut().send(root.clone()).await?;
+
+    let commitment = EncodingCommitment { root };
+
+    Ok((commitment, tree))
+}
+
+pub(crate) trait KeyStore {
+    fn delta(&self) -> &Delta;
+
+    fn get_keys(&self, data: Vector<U8>) -> Option<&[Key]>;
+}
+
+pub(crate) trait MacStore {
+    fn get_macs(&self, data: Vector<U8>) -> Option<&[Mac]>;
+}
+
+#[derive(Debug)]
+struct Provider {
+    sent: RangeMap<EncodingSlice>,
+    recv: RangeMap<EncodingSlice>,
+}
+
+impl EncodingProvider for Provider {
+    fn provide_encoding(
+        &self,
+        direction: Direction,
+        range: Range<usize>,
+        dest: &mut Vec<u8>,
+    ) -> Result<(), EncodingProviderError> {
+        let encodings = match direction {
+            Direction::Sent => &self.sent,
+            Direction::Received => &self.recv,
+        };
+
+        let encoding = encodings.get(range).ok_or(EncodingProviderError)?;
+
+        dest.extend_from_slice(encoding);
+
+        Ok(())
+    }
+}
+
+#[derive(Debug)]
+struct EncodingSlice(Vec<u8>);
+
+impl From<&[u8]> for EncodingSlice {
+    fn from(value: &[u8]) -> Self {
+        Self(value.to_vec())
+    }
+}
+
+impl Item for EncodingSlice {
+    type Slice<'a>
+        = &'a [u8]
+    where
+        Self: 'a;
+
+    fn length(&self) -> usize {
+        self.0.len() / ENCODING_SIZE
+    }
+
+    fn slice<'a>(&'a self, range: Range<usize>) -> Option<Self::Slice<'a>> {
+        self.0
+            .get(range.start * ENCODING_SIZE..range.end * ENCODING_SIZE)
+    }
+}
+
+/// Encoding protocol error.
+#[derive(Debug, thiserror::Error)]
+#[error(transparent)]
+pub struct EncodingError(#[from] ErrorRepr);
+
+#[derive(Debug, thiserror::Error)]
+#[error("encoding protocol error: {0}")]
+enum ErrorRepr {
+    #[error("I/O error: {0}")]
+    Io(std::io::Error),
+    #[error("incorrect MAC count for {direction}: expected {expected}, got {got}")]
+    IncorrectMacCount {
+        direction: Direction,
+        expected: usize,
+        got: usize,
+    },
+    #[error("encoding tree error: {0}")]
+    EncodingTree(EncodingTreeError),
+    #[error("unsupported hash algorithm: {0}")]
+    UnsupportedHashAlgorithm(HashAlgId),
+}
+
+impl From<std::io::Error> for EncodingError {
+    fn from(value: std::io::Error) -> Self {
+        Self(ErrorRepr::Io(value))
+    }
+}
+
+impl From<EncodingTreeError> for EncodingError {
+    fn from(value: EncodingTreeError) -> Self {
+        Self(ErrorRepr::EncodingTree(value))
+    }
+}

crates/tlsn/src/verifier/error.rs

@@ -2,6 +2,8 @@ use std::{error::Error, fmt};
 
 use mpc_tls::MpcTlsError;
 
+use crate::transcript_internal::commit::encoding::EncodingError;
+
 /// Error for [`Verifier`](crate::verifier::Verifier).
 #[derive(Debug, thiserror::Error)]
 pub struct VerifierError {
@@ -55,6 +57,7 @@ enum ErrorKind {
     Config,
     Mpc,
     Zk,
+    Commit,
     Verify,
 }
 
@@ -67,6 +70,7 @@ impl fmt::Display for VerifierError {
             ErrorKind::Config => f.write_str("config error")?,
             ErrorKind::Mpc => f.write_str("mpc error")?,
             ErrorKind::Zk => f.write_str("zk error")?,
+            ErrorKind::Commit => f.write_str("commit error")?,
             ErrorKind::Verify => f.write_str("verification error")?,
         }
 
@@ -101,3 +105,9 @@ impl From<MpcTlsError> for VerifierError {
         Self::new(ErrorKind::Mpc, e)
     }
 }
+
+impl From<EncodingError> for VerifierError {
+    fn from(e: EncodingError) -> Self {
+        Self::new(ErrorKind::Commit, e)
+    }
+}

crates/tlsn/src/verifier/verify.rs

@@ -14,12 +14,19 @@ use tlsn_core::{
 };
 
 use crate::{
-    transcript_internal::{TranscriptRefs, auth::verify_plaintext, commit::hash::verify_hash},
+    transcript_internal::{
+        TranscriptRefs,
+        auth::verify_plaintext,
+        commit::{
+            encoding::{self, KeyStore},
+            hash::verify_hash,
+        },
+    },
     verifier::VerifierError,
 };
 
 #[allow(clippy::too_many_arguments)]
-pub(crate) async fn verify<T: Vm<Binary> + Send + Sync>(
+pub(crate) async fn verify<T: Vm<Binary> + KeyStore + Send + Sync>(
     ctx: &mut Context,
     vm: &mut T,
     keys: &SessionKeys,
@@ -87,6 +94,11 @@ pub(crate) async fn verify<T: Vm<Binary> + Send + Sync>(
                 Direction::Sent => commit_sent.union_mut(idx),
                 Direction::Received => commit_recv.union_mut(idx),
             });
+
+        if let Some((sent, recv)) = commit_config.encoding() {
+            commit_sent.union_mut(sent);
+            commit_recv.union_mut(recv);
+        }
     }
 
     let (sent_refs, sent_proof) = verify_plaintext(
@@ -139,6 +151,24 @@ pub(crate) async fn verify<T: Vm<Binary> + Send + Sync>(
     sent_proof.verify().map_err(VerifierError::verify)?;
     recv_proof.verify().map_err(VerifierError::verify)?;
 
+    let mut encoder_secret = None;
+    if let Some(commit_config) = request.transcript_commit()
+        && let Some((sent, recv)) = commit_config.encoding()
+    {
+        let sent_map = transcript_refs
+            .sent
+            .index(sent)
+            .expect("ranges were authenticated");
+        let recv_map = transcript_refs
+            .recv
+            .index(recv)
+            .expect("ranges were authenticated");
+
+        let (secret, commitment) = encoding::transfer(ctx, vm, &sent_map, &recv_map).await?;
+        encoder_secret = Some(secret);
+        transcript_commitments.push(TranscriptCommitment::Encoding(commitment));
+    }
+
     if let Some(hash_commitments) = hash_commitments {
         for commitment in hash_commitments.try_recv().map_err(VerifierError::verify)? {
             transcript_commitments.push(TranscriptCommitment::Hash(commitment));
@@ -148,6 +178,7 @@ pub(crate) async fn verify<T: Vm<Binary> + Send + Sync>(
     Ok(VerifierOutput {
         server_name,
         transcript: request.reveal().is_some().then_some(transcript),
+        encoder_secret,
         transcript_commitments,
     })
 }

crates/tlsn/tests/test.rs

@@ -1,4 +1,5 @@
 use futures::{AsyncReadExt, AsyncWriteExt};
+use rangeset::set::RangeSet;
 use tlsn::{
     config::{
         prove::ProveConfig,
@@ -8,9 +9,12 @@ use tlsn::{
         verifier::VerifierConfig,
     },
     connection::ServerName,
-    hash::HashAlgId,
+    hash::{HashAlgId, HashProvider},
     prover::Prover,
-    transcript::{Direction, Transcript, TranscriptCommitConfig, TranscriptCommitmentKind},
+    transcript::{
+        Direction, Transcript, TranscriptCommitConfig, TranscriptCommitment,
+        TranscriptCommitmentKind, TranscriptSecret,
+    },
     verifier::{Verifier, VerifierOutput},
     webpki::{CertificateDer, RootCertStore},
 };
@@ -38,7 +42,7 @@ async fn test() {
 
     let (socket_0, socket_1) = tokio::io::duplex(2 << 23);
 
-    let ((_full_transcript, _prover_output), verifier_output) =
+    let ((full_transcript, prover_output), verifier_output) =
         tokio::join!(prover(socket_0), verifier(socket_1));
 
     let partial_transcript = verifier_output.transcript.unwrap();
@@ -54,6 +58,50 @@ async fn test() {
         partial_transcript.received_authed().iter().next().unwrap(),
         0..10
     );
+
+    let encoding_tree = prover_output
+        .transcript_secrets
+        .iter()
+        .find_map(|secret| {
+            if let TranscriptSecret::Encoding(tree) = secret {
+                Some(tree)
+            } else {
+                None
+            }
+        })
+        .unwrap();
+
+    let encoding_commitment = prover_output
+        .transcript_commitments
+        .iter()
+        .find_map(|commitment| {
+            if let TranscriptCommitment::Encoding(commitment) = commitment {
+                Some(commitment)
+            } else {
+                None
+            }
+        })
+        .unwrap();
+
+    let prove_sent = RangeSet::from(1..full_transcript.sent().len() - 1);
+    let prove_recv = RangeSet::from(1..full_transcript.received().len() - 1);
+    let idxs = [
+        (Direction::Sent, prove_sent.clone()),
+        (Direction::Received, prove_recv.clone()),
+    ];
+    let proof = encoding_tree.proof(idxs.iter()).unwrap();
+    let (auth_sent, auth_recv) = proof
+        .verify_with_provider(
+            &HashProvider::default(),
+            &verifier_output.encoder_secret.unwrap(),
+            encoding_commitment,
+            full_transcript.sent(),
+            full_transcript.received(),
+        )
+        .unwrap();
+
+    assert_eq!(auth_sent, prove_sent);
+    assert_eq!(auth_recv, prove_recv);
 }
 
 #[instrument(skip(verifier_socket))]
@@ -115,21 +163,25 @@ async fn prover<T: AsyncWrite + AsyncRead + Send + Unpin + 'static>(
 
     let mut builder = TranscriptCommitConfig::builder(prover.transcript());
 
-    let kind = TranscriptCommitmentKind::Hash {
-        alg: HashAlgId::SHA256,
-    };
-    builder
-        .commit_with_kind(&(0..sent_tx_len), Direction::Sent, kind)
-        .unwrap();
-    builder
-        .commit_with_kind(&(0..recv_tx_len), Direction::Received, kind)
-        .unwrap();
-    builder
-        .commit_with_kind(&(1..sent_tx_len - 1), Direction::Sent, kind)
-        .unwrap();
-    builder
-        .commit_with_kind(&(1..recv_tx_len - 1), Direction::Received, kind)
-        .unwrap();
+    for kind in [
+        TranscriptCommitmentKind::Encoding,
+        TranscriptCommitmentKind::Hash {
+            alg: HashAlgId::SHA256,
+        },
+    ] {
+        builder
+            .commit_with_kind(&(0..sent_tx_len), Direction::Sent, kind)
+            .unwrap();
+        builder
+            .commit_with_kind(&(0..recv_tx_len), Direction::Received, kind)
+            .unwrap();
+        builder
+            .commit_with_kind(&(1..sent_tx_len - 1), Direction::Sent, kind)
+            .unwrap();
+        builder
+            .commit_with_kind(&(1..recv_tx_len - 1), Direction::Received, kind)
+            .unwrap();
+    }
 
     let transcript_commit = builder.build().unwrap();