Cryptography II
Quantum Signatures and Protocol Extensions
Focuses on the overlay network and extending the protocol with quantum-resistant signatures.

Module overview
You will explore how rippled maintains a resilient peer-to-peer network and apply this knowledge to implement a Dilithium post-quantum signature amendment.
In this module
Understanding XRPL Overlay and Post-Quantum Signatures
This module includes a practical exploration: tracing the lifecycle of peer connections from discovery to disconnection, analyzing handshake protocols, message relaying, squelching optimizations, and peer discovery.
You will also implement Dilithium signature support and understand how post-quantum cryptography integrates with XRPL.
By the end, you will be able to read and modify production network and cryptographic code while maintaining protocol security.
Learning objectives
Overlay network
Understand architecture, peer connections, and resilience strategies.
Connection lifecycle
Trace full connection states from discovery to termination.
Handshake protocols
Analyze authentication, TLS, and protocol negotiation.
Message relaying
Explore broadcast, relay optimizations, and HashRouter integration.
Peer discovery
Learn bootstrapping, cache management, and endpoint evaluation.
Quantum-resistant signatures
Implement Dilithium and extend protocol signing.
Debugging and monitoring
Diagnose network and cryptographic issues in rippled.











