Commit Graph
15 Commits
Author SHA1 Message Date
Johnathan Corgan 6c90cf6c02 Implement Tor transport with operator visibility
Add TorTransport in src/transport/tor/ supporting three operating modes:

Outbound (socks5 mode):
- Non-blocking SOCKS5 connect via tokio-socks with per-destination
  circuit isolation (IsolateSOCKSAuth)
- TorAddr enum for .onion and clearnet address types
- Connection pool with per-connection receive tasks, reuses TCP
  stream FMP framing
- connect_async()/connection_state_sync()/promote_connection() follow
  the same non-blocking polling pattern as TCP transport

Inbound (directory mode — recommended for production):
- Tor manages the onion service via HiddenServiceDir in torrc
- FIPS reads .onion address from hostname file at startup
- No control port needed — enables Tor Sandbox 1 (seccomp-bpf)
- Accept loop mirrors TCP pattern with DirectoryServiceConfig

Monitoring (control_port mode and optional in directory mode):
- Async control port client supporting TCP and Unix socket connections
  via Box<dyn AsyncRead/Write> trait objects
- AUTHENTICATE with cookie or password auth
- 8 GETINFO queries: bootstrap, circuits, traffic, liveness, version,
  dormant state, SOCKS listeners
- Background monitoring task polls every 10s, caches TorMonitoringInfo
  in Arc<RwLock> for synchronous query access
- Bootstrap milestone logging (25/50/75/100%), stall warning (>60s),
  network liveness transitions, dormant mode entry
- Directory mode optionally connects to control port when control_addr
  is configured (non-fatal on failure)

Operator visibility:
- show_transports query exposes tor_mode, onion_address, tor_monitoring
  (bootstrap, circuit_established, traffic, liveness, version, dormant)
- fipstop transport detail view: Tor mode, onion address, SOCKS5/control
  errors, connection stats, Tor daemon status section
- fipstop table view: tor(mode) label with truncated onion address hint

Security hardening:
- Per-destination circuit isolation via IsolateSOCKSAuth
- Unix socket default for control port (/run/tor/control)
- Reference torrc with HiddenServiceDir, VanguardsLiteEnabled,
  ConnectionPadding, DoS protections (PoW + intro rate limiting)

Config:
- TorConfig with socks5, control_port, and directory modes
- DirectoryServiceConfig: hostname_file, bind_addr
- control_addr, control_auth, cookie_path, connect_timeout,
  max_inbound_connections

Testing:
- 69 unit + integration tests with mock SOCKS5 and control servers
- Docker tests: socks5-outbound (clearnet via Tor) and directory-mode
  (HiddenServiceDir onion service)

Documentation:
- Transport layer design doc: Tor architecture, directory mode
- Configuration doc: Tor config tables and examples
2026-03-15 16:19:54 +00:00
Johnathan Corgan c0f30d8fe8 Add DNS hostname support in peer addresses for UDP and TCP transports
Add resolve_socket_addr() with IP fast path and tokio::net::lookup_host()
fallback for DNS hostnames. Peer addresses can now use hostnames like
"peer1.example.com:2121" alongside IP addresses.

UDP transport adds a per-transport DNS cache (60s TTL) to avoid
per-packet resolution. TCP resolves at connect time (one-shot).

Update design docs, config examples, and changelog to reflect hostname
support in transport addressing.
2026-03-15 00:49:54 +00:00
Johnathan Corgan d873d0e00e Update design docs for non-blocking transport connect and cleanup stale references
- Rewrite TCP "Connect-on-Send" section to document non-blocking connect
  model (ConnectingPool, PendingConnect, poll_pending_connects)
- Add connect() and connection_state() to Transport trait surface
- Expand Connection Lifecycle section with ConnectionState enum
- Remove phantom TCP socks5_proxy field (removed from code, superseded
  by TorConfig)
- Fix "future Tor transport" references (stream reader already shared)
- Replace misleading "tor:" named TCP instance example
- Update fips-intro.md implementation status (TCP and Ethernet are
  implemented, not "under active design")
2026-03-13 16:37:00 +00:00
Johnathan Corgan f37eb4b846 Fix documentation drift from recent feature additions
Update 9 documentation files to match current implementation:
- Add missing rekey config section (node.rekey.*) and host mapping
  section to fips-configuration.md
- Update Ethernet frame format from [type:1][payload] to
  [type:1][length:2 LE][payload] in wire-formats and transport docs
- Fix Ethernet effective MTU from interface-1 to interface-3
- Mark rekey as Implemented in mesh-layer and session-layer status tables
- Change TCP default port examples from 443 to 8443
- Add rekey, persistent identity, host mapping, mesh size estimation to
  README features and status sections
- Update chaos scenario count from 16 to 20, add rekey topology to
  static test docs
2026-03-11 03:11:12 +00:00
Johnathan Corgan 56d39f223b Add ECN congestion signaling and transport congestion detection
Implement hop-by-hop ECN congestion signaling through the FMP layer,
transport-level congestion detection via kernel drop counters, and
chaos harness integration for end-to-end validation.

FMP/session ECN plumbing:

- Thread ce_flag parsed at link layer through dispatch_link_message,
  handle_session_datagram, handle_session_payload, and
  handle_encrypted_session_msg to session delivery
- Replace hardcoded false in session-layer record_recv() with actual
  ce_flag, activating ecn_ce_count tracking in session MMP

ECN congestion detection and CE relay:

- Add EcnConfig (node.ecn.*) with configurable loss_threshold (5%)
  and etx_threshold (3.0) for transit congestion detection
- Add send_encrypted_link_message_with_ce() that ORs FLAG_CE into FMP
  header flags; original method delegates with ce_flag=false
- Compute outgoing_ce = incoming_ce || local congestion on next-hop
  link, enabling hop-by-hop CE relay through transit nodes

IPv6 ECN-CE marking:

- Mark ECN-CE (0b11) in IPv6 Traffic Class on received DataPackets
  before TUN delivery when FMP CE flag is set
- Only marks ECN-capable packets (ECT(0)/ECT(1)); Not-ECT packets
  unchanged per RFC 3168

Transport congestion abstraction and UDP kernel drop detection:

- Add TransportCongestion struct to transport layer for transport-
  agnostic local congestion indicators
- Replace tokio::UdpSocket with AsyncFd<socket2::Socket> using
  libc::recvmsg() with ancillary data parsing
- Enable SO_RXQ_OVFL for kernel receive buffer drop counter on every
  packet, wiring up previously-stubbed UdpStats.kernel_drops
- Add TransportDropState for per-transport delta tracking with 1s
  tick sampling via sample_transport_congestion()
- Extend detect_congestion() with transport kernel drop check
  alongside MMP loss metrics

Congestion monitoring and control:

- Add CongestionStats (ce_forwarded, ce_received, congestion_detected,
  kernel_drop_events) to NodeStats with snapshot serialization
- Wire counters into forwarding path, session handler, and transport
  drop sampling with rate-limited warn logging (5s interval)
- Expose congestion data in show_routing control query and
  ecn_ce_count in show_mmp peer entries
- Add congestion counters to fipstop routing tab in two-column layout

Chaos harness integration:

- Add query_routing(), query_transports(), snapshot_all_congestion()
  to chaos control module
- Add congestion/kernel-drop log analysis in logs module
- Add congestion-stress scenario: 10-node tree, 1 Mbps bandwidth,
  5-10% netem loss, heavy iperf3 traffic
- Add IngressConfig for tc ingress policing with per-peer policer
  filters simulating upstream bandwidth bottlenecks
- Add iperf3 JSON result capture to traffic manager for throughput
  measurement across scenarios
- Add ECN A/B test scenarios (ecn-ab-on/off.yaml) with ingress
  policing and comparison script
- Enable TCP ECN negotiation (tcp_ecn=1 sysctl) in container
  entrypoint for end-to-end CE propagation

Tests:

- 10 ECN unit/integration tests: mark_ipv6_ecn_ce variants, CE relay
  chain (3-node propagation), EcnConfig serde roundtrip
- 3 transport drop congestion detection unit tests

Documentation:

- Update fips-mesh-layer.md: replace outdated CE Echo stub with full
  ECN Congestion Signaling section covering detection logic, CE relay,
  IPv6 marking, session tracking, and monitoring counters
- Update fips-configuration.md: add node.ecn.* parameter table and
  ecn block in complete reference YAML
- Update fips-transport-layer.md: add Congestion Reporting section
  with TransportCongestion struct, congestion() trait method, and
  per-transport status; document AsyncFd/recvmsg/SO_RXQ_OVFL in UDP
- Update chaos README: add congestion/ECN scenario docs, ingress
  traffic control, and iperf3 JSON capture sections
- Update README.md: add ECN to features list and "What works today";
  update transport and tooling entries
2026-03-05 17:05:57 +00:00
Johnathan Corgan ec64a0dce1 Add TCP transport implementation and test harness support
Implement TCP transport for FIPS enabling firewall traversal and serving
as the foundation for future Tor transport. This is the first
connection-oriented transport in the system.

Key design decisions:
- FMP header-based framing: reuses existing 4-byte FMP common prefix for
  packet boundary recovery with zero framing overhead
- Session survives TCP reconnection: Noise/MMP/FSP state bound to npub,
  not TCP connection; MMP liveness is sole authority for peer death
- Connect-on-send: fresh connection on first send, transparent reconnect
- close_connection() trait method for cross-connection deduplication cleanup

New transport files:
- src/transport/tcp/mod.rs: TcpTransport, connection pool, accept loop
- src/transport/tcp/stream.rs: FMP-aware stream reader (shared with Tor)

Modified: transport trait (close_connection), TcpConfig, TransportHandle
match arms, create_transports(), initiate_connection() for connection-
oriented links, cross-connection tie-breaker cleanup, design docs.

Tree announce loop and TCP stability fixes:
- Preserve tree announce rate-limit state across reconnection: carry
  forward last_tree_announce_sent_ms when a peer reconnects so the
  rate-limit window isn't reset to zero
- Drop oversize TCP packets at sender: pre-send MTU check returns
  MtuExceeded instead of writing to the stream, preventing receiver-side
  connection teardown and reset-reconnect cycles

Chaos harness:
- TCP transport support: tcp_edges/has_tcp/tcp_peers in SimTopology,
  transport-aware config_gen with per-edge transport type, TCP port 443,
  pure-TCP node support
- Include all non-Ethernet edges in directed_outbound()
- Fix netem/links log messages to say "IP-based" instead of "UDP"
- Add tcp-chain, tcp-only, and tcp-mesh scenario files

Static harness:
- Transport-aware config generation (get_default_transport, transport_port)
- TCP transport injection via Python post-processing
- Add tcp-chain topology and docker-compose profile
2026-02-27 00:41:37 +00:00
Johnathan Corgan daf1e629df Change default UDP port to 2121 and EtherType to 0x2121
Update the default UDP bind port from 4000 to 2121 (decimal) and the
default Ethernet EtherType from 0x88B5 to 0x2121 across all source
code, documentation, configuration templates, test fixtures, and
scripts. Remove references to "IEEE 802 experimental range" since
0x2121 is not in that range.
2026-02-26 13:22:09 +00:00
Johnathan Corgan d29da442ac Add Ethernet transport with beacon discovery
Implement raw Ethernet transport using AF_PACKET SOCK_DGRAM on Linux
with EtherType 0x88B5 (IEEE experimental range) and 1-byte frame type
prefix (0x00=data, 0x01=beacon).

Transport implementation:
- EthernetConfig with interface, ethertype, MTU, buffer sizes, and
  four independent discovery knobs (discovery, announce, auto_connect,
  accept_connections)
- PacketSocket/AsyncPacketSocket wrappers with ioctl helpers for
  interface index, MAC address, and MTU queries
- EthernetTransport with Transport trait impl, async start/stop/send,
  receive loop dispatching data frames and discovery beacons
- Discovery beacons (34 bytes: type + version + x-only pubkey) with
  DiscoveryBuffer for peer accumulation and dedup
- Atomic statistics counters (frames, bytes, errors, beacons)
- Platform-gated with #[cfg(target_os = "linux")]

Transport-layer discovery integration:
- Promote auto_connect() and accept_connections() to Transport trait
  with default implementations and TransportHandle dispatch
- Extract initiate_connection() so both static peer config and
  discovery auto-connect share the same handshake initiation path
- Add poll_transport_discovery() to the tick handler to drain
  discovery buffers and auto-connect to discovered peers
- Enforce accept_connections() in handle_msg1() — transports with
  accept_connections=false silently drop inbound handshakes

Node integration:
- create_transports() handles Ethernet named instances
- resolve_ethernet_addr() parses "interface/mac" address format
- transport_mtu() generalized for multi-transport operation

Test harness:
- VethPair RAII struct for veth pair lifecycle management
- Three #[ignore] integration tests requiring root/CAP_NET_RAW:
  two-node handshake, data exchange, mixed transport coexistence
- Chaos harness: transport-aware topology model, VethManager for
  veth pairs between Docker containers, Ethernet-aware config gen,
  netem split (HTB+u32 for UDP, root netem for veth), transport-aware
  link flaps and node churn with veth re-setup
- Container entrypoint waits for configured Ethernet interfaces
  before starting FIPS (handles veth creation timing)
- New scenarios: ethernet-only (4-node ring), ethernet-mesh (6-node
  mixed UDP+Ethernet with netem and link flaps)

Documentation:
- fips-transport-layer.md: Ethernet section, beacon discovery, WiFi
  compatibility, updated discovery state, trait surface additions,
  implementation status table
- fips-configuration.md: Ethernet parameter table, named instances,
  peer address format, mixed UDP+Ethernet example, complete reference
- fips-wire-formats.md: Ethernet frame type prefix note
2026-02-26 00:03:14 +00:00
Johnathan Corgan 00e26765bd Design documentation illustration and review pass
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
2026-02-24 17:32:37 +00:00
Johnathan Corgan 0d93a19e07 Implement cost-based parent selection with periodic re-evaluation
Cost-based parent selection:
- Replace depth-only parent selection with effective_depth = depth + link_cost
- link_cost computed from locally measured MMP metrics: etx * (1.0 + srtt_ms / 100.0)
- Prevents bottleneck subtrees in heterogeneous networks where a LoRa link
  at depth 1 would otherwise always beat fiber at depth 2
- Configurable hysteresis (default 0.2) prevents marginal parent switches
- Configurable hold-down timer (default 30s) suppresses re-evaluation
  after parent switch
- Mandatory switches (parent lost, root change) bypass both safeguards
- Link costs passed as HashMap parameter to keep TreeState pure

Periodic re-evaluation:
- evaluate_parent() was only called on TreeAnnounce receipt or parent loss;
  after tree stabilization, link degradation went undetected
- Added timer-based re-evaluation (reeval_interval_secs, default 60s) that
  calls evaluate_parent() from the tick handler with current MMP link costs
- Respects existing hold-down and hysteresis safeguards
- Short-circuits when disabled or <2 peers

Design documentation:
- Update 7 design docs to reflect cost-based parent selection
- Replace depth-only algorithm descriptions with effective_depth model
- Replace rejected cumulative path cost spec with local-only design rationale
- Rewrite Example 2 (heterogeneous links) for local-only cost model
- Update config docs: parent_switch_threshold replaced by parent_hysteresis,
  hold_down_secs, reeval_interval_secs

Chaos simulation enhancements:
- fips_overrides with deep merge for per-scenario FIPS config customization
- Explicit topology algorithm for deterministic test graphs
- Control socket querying via fipsctl for tree/MMP snapshot collection
- Edge existence validation in netem manager
- Per-link netem policy overrides
- 9 new chaos scenarios covering cost avoidance, depth-vs-cost tradeoffs,
  stability, mixed topologies, periodic re-evaluation, and bottleneck parent

12 new unit tests, 667 total passing, clippy clean.
2026-02-23 17:15:20 +00:00
Johnathan Corgan dc89edf60b Update design docs for session 142 implementation changes
Comprehensive documentation review across 12 files to reflect:
- Noise XK at FSP (was IK), 3-message handshake, SessionMsg3 wire format
- Epoch exchange in Noise handshakes for peer restart detection
- Per-link MTU, min_mtu/path_mtu in lookup packets
- MtuExceeded (0x22) error signal wire format and behavior
- LookupResponse proof now covers target_coords
- Discovery reverse-path routing as primary (not greedy)
- Control socket architecture and fipsctl binary
- FSP handshake state machine (Initiating/AwaitingMsg3/Established)
- Root timeout framing updated for heartbeat cascading
2026-02-22 23:03:00 +00:00
Johnathan Corgan 0a72317b59 Design documentation illustration pass and FLP→FMP rename
Rename FIPS Link Protocol (FLP) to FIPS Mesh Protocol (FMP)

  The "Link Protocol" name understated the layer's scope — spanning tree
  construction, bloom filter routing, greedy forwarding, and mesh-wide
  coordination go well beyond link-level concerns. Rename fips-link-layer.md
  to fips-mesh-layer.md, update FLP→FMP throughout docs and source code
  (FLP_VERSION→FMP_VERSION, wire.rs, rx_loop.rs, spanning_tree.rs).

New SVG illustrations

  - Protocol stack: color-coded layer diagram replacing ASCII art
  - OSI mapping: side-by-side comparison with traditional networking layers
  - Bloom filter propagation: 6-node tree with sender-colored filter boxes
    showing split-horizon computation per link
  - Routing decision flowchart: 5-step priority chain with candidate ranking
    by tree distance and link performance
  - Coordinate discovery: sequence diagram showing LookupRequest propagation,
    response caching, and SessionSetup cache warming

Redesigned existing SVGs

  - Architecture overview: uniform node layout, U-shaped encrypted link
    connectors, separate end-to-end session line
  - Node architecture: split Router Core into FSP and FMP layers, reorganize
    transports into Overlay/Shared Medium/Point-to-Point categories
  - Identity derivation: wider boxes, visible encode arrow, dashed npub line

fips-intro.md revisions

  - Add inline references to prior work: Yggdrasil/Ironwood for coordinate
    routing, Noise Protocol Framework for IK handshakes, WireGuard for
    index-based session dispatch, Wikipedia for bloom filters, split-horizon,
    and greedy embedding
  - Add explanatory paragraphs after bloom filter diagram describing
    split-horizon filter computation and candidate selection behavior
  - Simplify transport abstraction language, remove I2P/LoRa references
  - Fix LookupRequest wording ("propagates" not "floods"), note intermediate
    node coordinate caching on lookup responses
  - Rewrite architecture overview prose to match redesigned diagrams
2026-02-21 22:05:44 +00:00
Johnathan Corgan 7df1f21429 Design documentation refresh: MMP, wire formats, and configuration alignment
Bring all 9 design documents into alignment with the current
implementation. Major additions include MMP coverage at both link and
session layers, wire format tables for SenderReport and ReceiverReport,
UDP socket buffer sizing, PathMtuNotification status updates, and
configuration parameter fixes (default_ttl key name, idle timeout MMP
exclusion semantics).
2026-02-19 06:45:46 +00:00
Johnathan Corgan d8cb4d407e FLP wire format revision and MMP link-layer measurement protocol
## FLP Wire Format Revision

Replace the 1-byte discriminator with a structured wire format:

- 4-byte common prefix (ver+phase, flags, payload_len) and 16-byte
  established frame header with AEAD AAD binding
- 5-byte encrypted inner header (4-byte session-relative timestamp +
  1-byte message type) on all link messages
- Phase-based packet dispatch replacing discriminator-based dispatch
- SessionDatagram reassigned from type 0x40 to 0x00; add SenderReport
  (0x01) and ReceiverReport (0x02) message types for MMP
- SessionDatagram: rename hop_limit to ttl, add path_mtu field (u16 LE)
  with min(datagram.path_mtu, transport.mtu()) at forwarding
- Updated handshake packets (msg1: 87->90 bytes, msg2: 42->45 bytes)
- FIPS_OVERHEAD updated from 135 to 144 bytes

## MMP Link-Layer Measurement Protocol

Add the Metrics Measurement Protocol for link quality measurement
between FIPS peers. Measures RTT, loss, jitter, throughput, OWD trend,
and ETX from periodic sender/receiver reports exchanged over established
links.

Module layout:
- mmp/algorithms.rs: JitterEstimator, SrttEstimator, DualEwma, OwdTrend,
  SpinBit, ETX computation
- mmp/report.rs: SenderReport (48B) and ReceiverReport (68B) wire format
- mmp/sender.rs: per-peer TX counters and interval tracking
- mmp/receiver.rs: per-peer RX counters, jitter, loss, gap tracking
- mmp/metrics.rs: derived metrics from report processing (SRTT, goodput_bps)
- mmp/mod.rs: MmpMode (Full/Lightweight/Minimal), MmpConfig, MmpPeerState
- node/handlers/mmp.rs: report dispatch, timer-driven generation, operator
  logging (periodic + teardown)

Integration: per-frame TX/RX hooks in encrypted message handling, report
dispatch from link message router, timer-driven generation from tick
handler, and periodic operator logging with throughput formatting.

Three operating modes: Full (sender + receiver reports, spin bit, CE echo),
Lightweight (receiver reports only), Minimal (spin bit + CE echo only).

## Design Documentation

Updated FLP sections across all design documents to match the implemented
wire format, including revised overhead calculations and numeric values.

568 tests pass, clippy clean.
2026-02-18 21:54:21 +00:00
Johnathan Corgan d46dc874ef Restructure design docs around protocol layers
Reorganize FIPS design documentation from implementation-centric
structure (routing, gossip protocol, wire protocol, transports) to
protocol-layer organization with clear service boundaries.

New documents (8):
- fips-transport-layer.md — transport layer spec
- fips-link-layer.md — FLP spec (peer auth, link encryption, forwarding)
- fips-session-layer.md — FSP spec (end-to-end encryption, sessions)
- fips-ipv6-adapter.md — IPv6 adaptation (TUN, DNS, MTU enforcement)
- fips-mesh-operation.md — routing, discovery, error recovery
- fips-wire-formats.md — consolidated wire format reference
- fips-spanning-tree.md — tree algorithm reference
- fips-bloom-filters.md — bloom filter math reference

Rewritten (2):
- fips-intro.md — breadth-first intro with layer model diagrams
- fips-software-architecture.md — slimmed to stable decisions

Updated (3):
- spanning-tree-dynamics.md — removed stale root refresh, aligned terminology
- fips-configuration.md — fixed priority type (u16 → u8)
- fips-state-machines.md — synced code examples with codebase

Deleted (6): fips-transports.md, fips-wire-protocol.md,
fips-gossip-protocol.md, fips-session-protocol.md, fips-routing.md,
fips-tun-driver.md (content absorbed into new structure)
2026-02-17 04:50:04 +00:00