entangl
Agents are already buying ads, booking travel, and moving money on behalf of humans over messages protected by cryptography that a quantum computer will break, while harvest-now-decrypt-later adversaries record everything today.
A live four-message buyer/seller negotiation completes in 1.40 s with every message encrypted under ML-KEM-1024 (FIPS 203) and signed with ML-DSA-87 (FIPS 204), the relay reading zero payload bytes, rogue agents blocked, and tampered messages rejected.
The problem
The agentic web is arriving: agents negotiate compute, book travel, and execute financial transactions on behalf of humans. Today those machine-to-machine messages are protected by RSA and elliptic-curve cryptography — algorithms mathematically broken by a sufficiently large quantum computer running Shor’s algorithm. Nation-state adversaries are already running harvest-now-decrypt-later attacks: recording encrypted agent traffic now to decrypt once quantum hardware matures.
Approach
Entangl is a post-quantum secure communication protocol purpose-built for agent-to-agent messaging. The stack layers ML-DSA-87 identity (NIST FIPS 204, derived from CRYSTALS-Dilithium), ML-KEM-1024 forward-secret per-message encryption (NIST FIPS 203, derived from CRYSTALS-Kyber), AES-256-GCM with BLAKE2b-HKDF symmetric crypto, an optional BB84 QKD layer (via Cirq, information-theoretic security), and WebSocket/gRPC transport. Every send() generates a fresh ML-KEM-1024 encapsulation, encrypts with AES-256-GCM, and signs with ML-DSA-87; the routing server cannot read message content.
Evidence
The repo’s live demo runs a complete buyer/seller negotiation: four messages (PROPOSE, COUNTER, ACCEPT, CONFIRM) completing a GPU-compute deal in 1.40 s, with the server reading zero bytes of payload content, rogue agents blocked, and tampered messages rejected — signature verified and decryption OK on every hop. ML-KEM-1024 encapsulations are 1568-byte ciphertexts; ML-DSA-87 signatures are 4595 bytes. The SDK ships a Python client, a runnable server, and an integration test, installable with pip install entangl.