mirror of
https://github.com/jmcorgan/fips.git
synced 2026-10-06 03:28:24 +00:00
Johnathan Corgan
32bf476660
A tree announce was counted as delivered once the transport accepted it, so a lost datagram left the peer on our old tree position until the periodic re-broadcast up to a minute later, and indefinitely on a node with a single peer, which has no periodic re-broadcast. Meanwhile the peer could leave destinations out of discovery or route toward them by stale coordinates. The tree state now keeps, per peer, the tree announce still awaiting confirmation from the link's receiver reports, using the same delivery check as filter announces. The declaration sequence is the lineage: a new sequence refills the resend budgets, while a resend or periodic re-broadcast of the same declaration spends from them. The tracking is dropped with the peer. The node resends on a reported loss, and once after 30 s when the reports cannot confirm the announce. Per declaration and session it resends at most once unchecked and three times on loss, and at most six times a minute per peer. The resend is an ordinary announce of the current declaration through the rate-limited send path, and the "Sent TreeAnnounce" trace line now carries the declaration sequence. The node tests run on a converged line with every role read from the converged tree, and share the loopback MMP, loss and rekey helpers of the filter announce tests, now generalised to node indices. The Ethernet mesh scenario's 60 s delivery window no longer sits at the ordinary recovery bound, since tree and filter announces lost to a link flap are now resent within seconds of the link returning, or after about 30 s when the reports cannot confirm them. A comment beside the assertion says so, so a red there is investigated rather than expected.
FIPS Design
Architectural and protocol-level explanations for FIPS — the why and the how behind the wire and the system. For wire formats and configuration keys, see reference/. For task recipes, see how-to/. For end-to-end lessons, see tutorials/.
Reading Order
Start with fips-concepts.md for the novice-friendly framing of what FIPS is and why, then move to fips-architecture.md for the protocol stack, identity model, and two-layer encryption walkthrough. From there, follow the protocol stack from bottom to top. After the stack, fips-mesh-operation.md explains how the pieces work together at runtime. Cross-cutting and supporting documents cover specific subsystems in detail.
Foundations
| Document | Description |
|---|---|
| fips-concepts.md | What FIPS is, why it exists, mental model |
| fips-architecture.md | Protocol stack, identity, two-layer encryption |
| fips-prior-work.md | Designs and protocols FIPS builds on |
Protocol Stack
| Document | Description |
|---|---|
| fips-transport-layer.md | Transport layer: datagram delivery over arbitrary media |
| fips-mesh-layer.md | FIPS Mesh Protocol (FMP): peer authentication, link encryption, forwarding |
| fips-session-layer.md | FIPS Session Protocol (FSP): end-to-end encryption, sessions |
| fips-ipv6-adapter.md | IPv6 adaptation: TUN interface, DNS, MTU enforcement |
| fips-native-api.md | Native datagram API: pubkey-addressed flows over FSP, and what it is instead of the TUN path |
Cross-Cutting
| Document | Description |
|---|---|
| fips-mmp.md | Metrics Measurement Protocol (link + session) |
| fips-mtu.md | Path MTU model, encapsulation overhead, PMTUD |
| fips-security.md | fips0 interface threat model and default-deny baseline |
Mesh Behavior
| Document | Description |
|---|---|
| fips-mesh-operation.md | How the mesh operates: routing, discovery, error recovery |
| fips-nostr-discovery.md | Optional Nostr-mediated peer discovery and UDP NAT hole-punch |
| port-advertisement-and-nat-traversal.md | Nostr-signaled port advertisement and UDP NAT-traversal protocol; generic, with FIPS as an example implementation |
Deeper Dives
| Document | Description |
|---|---|
| fips-spanning-tree.md | Spanning tree algorithms: root discovery, parent selection, coordinates |
| fips-bloom-filters.md | Bloom filter properties: FPR analysis, size classes, split-horizon |
| spanning-tree-dynamics.md | Spanning tree walkthroughs: convergence scenarios, worked examples |
Adjacent Components
| Document | Description |
|---|---|
| fips-gateway.md | fips-gateway service: outbound (LAN-to-mesh) DNS-proxy + virtual-IP NAT and inbound (mesh-to-LAN) port-forwarding, sharing one nftables table |