Files
fips/docs/design
Johnathan Corgan 7dc0b7fc52 Session 53: Route cache warming and session protocol refinements
Session protocol (fips-session-protocol.md):
- Clarified DNS entry point applies to IP-based apps; native FIPS uses npub
- Updated transport failover examples (UDP → WiFi, WiFi → LTE)
- Added roaming description to session independence section
- Expanded §5 with coords-on-demand mechanism for route cache recovery
- Added Noise IK vs XK privacy tradeoff note to §6

Routing (fips-routing.md):
- DataPacket now has optional coordinates (COORDS_PRESENT flag)
- Updated handle_data_packet to cache coords from packets
- Sender state machine: WARM/COLD based on CoordsRequired errors
- Updated packet type summary table

Architecture (fips-architecture.md):
- Fixed cross-references to session protocol sections
2026-02-02 03:39:13 +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