Wire format diagrams: - Add 24 SVG diagrams covering every FMP and FSP wire format: common prefix, established frame headers, Noise IK handshake messages, handshake flow, TreeAnnounce, AncestryEntry, FilterAnnounce, LookupRequest/Response, SessionDatagram, Disconnect, SenderReport, ReceiverReport, FSP complete message, SessionSetup/Ack/Msg3, PathMtuNotification, CoordsRequired, PathBroken, and MtuExceeded - Replace ASCII art in fips-wire-formats.md with SVG references - Apply text edits to fips-mesh-layer.md, fips-mesh-operation.md, fips-transport-layer.md, and fips-ipv6-adapter.md Spanning tree dynamics: - Add 12 topology SVG diagrams: node join (overview + 3-panel steps), three-node convergence (4-panel), link addition with depth labels, link removal, partition formation, and 6 real-world example diagrams (office, mixed-link, two-site WAN topologies) - Rewrite all code blocks to narrative prose with diagram references - Add inline prior art attributions distinguishing Yggdrasil-derived concepts from FIPS-novel contributions - Add 3 new references (De Couto ETX, IEEE 802.1D, RFC 2328 OSPF) and Prior Art summary - Remove outdated sections: indirect partition note, integration test gaps, DHT-based lookup reference - Change "must elect a new root" to "must rediscover its new root" Spanning tree design review (fips-spanning-tree.md): - Rename "Root Election" to "Root Discovery" across docs - Add "What Is a Spanning Tree?" introductory section - Add parent selection intro explaining self-organization role - Fix tree distance example: 4 hops, not 2 - Clarify timestamp field as advisory only - Remove unimplemented ROOT_TIMEOUT and TREE_ENTRY_TTL from timing parameters and implementation status tables Bloom filter design review (fips-bloom-filters.md): - Add "What Is a Bloom Filter?" intro section - Rewrite Purpose section to frame filters as routing path identification - Correct FPR analysis (old values were 3-50x overstated) - Add Filter Occupancy Model based on network size and tree position - Fix filter expiration to describe actual MMP-based cleanup - Combine Scale Considerations with Size Classes after Wire Format - Fix stale FPR values in src/bloom/mod.rs comments Session layer review (fips-session-layer.md): - Add inline prior art attributions: Noise Protocol Framework, WireGuard, DTLS (RFC 6347), IKEv2 (RFC 7296), RFC 1191 PMTUD, Yggdrasil, NIP-44 - Replace warmup state machine ASCII art with SVG diagram - Convert CoordsWarmup wire format code block to prose - Add External References section with full citations Level 5 implementation doc cleanup: - Delete fips-software-architecture.md (redundant with protocol layer docs) - Delete fips-state-machines.md (Rust tutorial, not protocol design) - Add fipsctl command reference to README.md - Update cross-references in fips-intro.md, docs/design/README.md, fips-transport-layer.md, fips-configuration.md Fixes: - Correct fd::/8 to fd00::/8 in fips-session-layer.md, fips-identity-derivation.svg, and fips-node-architecture.svg - Fix config example MTU: 1197 → 1472 in fips-configuration.md File organization: - Move all SVG diagrams into docs/design/diagrams/ subdirectory - Update all diagram references to use new paths
FIPS: Free Internetworking Peering System
A distributed, decentralized network routing protocol for mesh nodes connecting over arbitrary transports.
Status: Experimental / Pre-release
FIPS is under active development. The protocol and APIs are not stable. Expect breaking changes.
Overview
FIPS is a self-organizing mesh network that operates natively over a variety of physical and logical media — local area networks, Bluetooth, serial links, radio, or the existing internet as an overlay. Nodes generate their own identities, discover each other, and route traffic without any central authority or global topology knowledge.
FIPS uses Nostr keypairs (secp256k1/schnorr) as native node identities, making every Nostr user a potential network participant. Nodes address each other by npub, and the same cryptographic identity used in the Nostr ecosystem serves as both the routing address and the basis for end-to-end encrypted sessions across the mesh.
Features
- Self-organizing mesh routing — spanning tree coordinates and bloom filter candidate selection, no global routing tables
- Multi-transport — UDP/IP overlay today; designed for Ethernet, Bluetooth, serial, radio, and Tor
- Noise encryption — hop-by-hop link encryption plus independent end-to-end session encryption
- Nostr-native identity — secp256k1 keypairs as node addresses, no registration or central authority
- IPv6 adaptation — TUN interface maps npubs to fd00::/8 addresses for unmodified IP applications
- Metrics Measurement Protocol — per-link RTT, loss, jitter, and goodput measurement
- Operator visibility —
fipsctlcontrol socket interface for runtime inspection of peers, links, sessions, tree state, and metrics - Zero configuration — sensible defaults; a node can run with no config file
Quick Start
Requirements
- Rust 1.85+ (edition 2024)
- Linux (TUN interface requires
CAP_NET_ADMINor root)
Build
git clone https://github.com/jmcorgan/fips.git
cd fips
cargo build --release
Run
# With default configuration (ephemeral identity, default ports):
sudo ./target/release/fips
# With a configuration file:
sudo ./target/release/fips -c fips.yaml
See docs/design/fips-configuration.md for the full configuration reference.
Inspect
While a node is running, use fipsctl to inspect its state:
fipsctl show status # Node status overview
fipsctl show peers # Authenticated peers
fipsctl show links # Active links
fipsctl show tree # Spanning tree state
fipsctl show sessions # End-to-end sessions
fipsctl show bloom # Bloom filter state
fipsctl show mmp # MMP metrics summary
fipsctl show cache # Coordinate cache stats
fipsctl show connections # Pending handshake connections
fipsctl show transports # Transport instances
fipsctl show routing # Routing table summary
fipsctl communicates with the node via a Unix domain control socket
(enabled by default). All queries are read-only. Use -s <path> to
override the socket path.
Multi-node Testing
See testing/ for Docker-based integration test harnesses including static topology tests and stochastic chaos simulation.
Documentation
Protocol design documentation is in docs/design/, organized as a layered protocol specification. Start with fips-intro.md for the full protocol overview.
Project Structure
src/ Rust source (library + fips/fipsctl binaries)
docs/design/ Protocol design specifications
testing/ Docker-based integration test harnesses
benches/ Criterion benchmarks
License
MIT — see LICENSE.