Files
fips/docs/design
Johnathan Corgan 1c2cda480d Implement spanning tree announcement send/receive protocol
Add TreeAnnounce v1 wire format with versioned encoding (version byte
0x01), slim ancestry entries (32 bytes each, no per-entry signatures),
and transitive trust model where only the direct peer's declaration
signature is verified.

Key changes:
- Enrich TreeCoordinate with CoordEntry metadata (sequence, timestamp)
- TreeAnnounce encode/decode with roundtrip tests
- Per-peer rate limiting (500ms minimum interval) on ActivePeer
- Parent selection: depth-based algorithm with broken-path detection
- New node/tree.rs module: send/receive, periodic refresh, cleanup
- Wire up dispatch, initial announce on promotion, tick integration
- Update gossip protocol design doc with trust model (§2.7)

304 tests pass, clean build.
2026-02-10 23:35:09 +00:00
..

FIPS Design Documents

Protocol design specifications and analysis for the Federated Interoperable Peering System.

Suggested Reading Order

Start with the high-level architecture, then work through session flow, routing concepts, and finally the wire-level protocol details.

1. Introduction and Overview

Document Description
fips-intro.md Protocol introduction: goals, concepts, architecture

2. Protocol Flow (How Traffic Works)

Document Description
fips-session-protocol.md End-to-end session flow, Noise IK encryption, terminology

3. Routing (How Packets Find Their Way)

Document Description
fips-routing.md Routing concepts: bloom filters, discovery, greedy routing
spanning-tree-dynamics.md Tree protocol behavior: convergence, partitions, recovery
fips-gossip-protocol.md Wire formats: TreeAnnounce, FilterAnnounce, Lookup messages
Document Description
fips-wire-protocol.md Transport layer: Noise IK, session indices, roaming, security
fips-transports.md Transport-specific: UDP, Ethernet, Tor, radio characteristics

Implementation

Document Description
fips-architecture.md Software architecture: entities, state machines, configuration
fips-tun-driver.md TUN interface driver: reader/writer threads, ICMPv6, packet flow
fips-state-machines.md Phase-based state machine pattern: peer lifecycle, transitions

Document Cross-References

                      fips-intro.md
                           │
              ┌────────────┴────────────┐
              ▼                         ▼
    fips-session-protocol.md    fips-architecture.md
              │                         │
    ┌─────────┴─────────┐               ▼
    ▼                   ▼         fips-transports.md
fips-routing.md   fips-wire-protocol.md
    │       │
    ▼       ▼
spanning-tree-dynamics.md ←→ fips-gossip-protocol.md