flowchart TD
    subgraph HostLayer["Host 构建层"]
        Key["Ed25519 Peer Key / KeyManager"] --> Host["LibP2PHost"]
        Host --> Transport["TCP + QUIC"]
        Host --> Security["Noise primary / TLS fallback"]
        Host --> Muxer["yamux"]
        Host --> Gater["ConnectionGater + DefenseSystem"]
        Host --> Bandwidth["BandwidthCounter"]
    end

    subgraph DiscoveryLayer["发现与接入层"]
        Host --> AutoNAT["AutoNAT Reachability"]
        Host --> MDNS["mDNS"]
        Host --> RelayBootstrap["connectToBootstrapRelays"]
        RelayBootstrap --> RelayNodes["GatewayURL -> Public Relay Nodes"]
        L1["DiscoveryManager: Contract / DHT / DNS / mDNS / Seed"] --> PeerBook["PeerBook"]
        Host --> PeerBook
    end

    subgraph MessageLayer["消息传播层"]
        PeerBook --> DHT["LibP2PDiscovery / Kademlia DHT"]
        DHT --> Gossip["LibP2PPubSub / GossipSub"]
        Gossip --> Blocks["Topic: blocks"]
        Gossip --> Txs["Topic: txs"]
        Gossip --> Validators["Topic: validators 或 consensus"]
        PeerBook --> Stream["LibP2PStreamMessenger"]
        Stream --> Sync["BlockRequest / BlockResponse / BlockSyncManager"]
    end

    subgraph Runtime["节点运行时"]
        Quantum["Quantum Node"] --> Host
        Quantum --> DHT
        Quantum --> Gossip
        Quantum --> Stream
        Gossip --> Broadcast["区块 / 交易 / 验证者广播"]
        Sync --> Catchup["缺块直连拉取与同步"]
    end