Decentralized Peer-to-Peer Network Layer
1. Network Design Objectives
The ANCORA P2P network is designed for:
Global scalability to 100,000+ nodes
Byzantine fault tolerance against adversarial nodes
Resistance to Sybil, eclipse, and DDoS attacks
Low latency block and transaction propagation
Censorship resistance and geographic distribution
Post-quantum secure transport encryption
The network is built on libp2p with custom extensions for blockchain-specific requirements.
2. Core Network Stack
2.1 Transport Layer
Primary Transport: QUIC over UDP
Fallback Transport: TCP + TLS 1.3
Encryption: CRYSTALS-Kyber 768 post-quantum key exchange + AES-256-GCM
Multiplexing: Yamux stream multiplexing
NAT Traversal: AutoNAT + Hole punching + Relay nodes
2.2 Node Discovery
Distributed Hash Table: Kademlia DHT with 20-bit keyspace
Bootstrap Nodes: 20 geographically distributed permanent bootstrap nodes
Peer Exchange (PEX): Gossiped peer address exchange
MDNS: Local network peer discovery
2.3 Messaging Protocol
All messages use Protobuf encoding with signed message authentication:
3. Attack Mitigation
3.1 Sybil Attack Resistance
Node identity bound to stake weight
Minimum stake requirement for full node status
Peer scoring system with reputation tracking
Geographic and ASN diversity enforcement
IP rate limiting with exponential backoff
3.2 Eclipse Attack Resistance
Minimum 8 outbound peer requirement
Mandatory peer diversity across ASNs and geographies
Random peer churn every 24 hours
Peer connection limit per /24 subnet
Bootstrap node redundancy across 15+ countries
3.3 DDoS Attack Resistance
Transaction and block rate limiting per peer
Proof of bandwidth requirement for connection initiation
Adaptive peer banning for misbehavior
Distributed relay node network
Message size limits and validation