09/09/26 Bi-Weeky libp2p Spec Meeting

[johannamoran]

Attendees

@seetadev
@johannamoran
@richard-ramos
@gmelodie (Gabriel)
@yiannisbot
@flcl42

Spec Lifecycle Stages

1. RFC [piloting]
2. Working Draft [POC in implement + Spec PR]
3. Candidate recommendation [ >2 implementations with interop recommended]
4. Recommendation [> 3 implementations and interop completed with applicable]

---

AGENDA

1. NEW PRs requesting review and feedback
2. Existing PRs updates
3. Spec PRs ready to merge
4. AOB

Spec Ops priorities before next bi-weekly

Outreach to Spec authors

• WebRTC pr merge docs: webrtc-direct-v2 #715
• Request @gmelodie feedback on PR 701
• Request @tabcat approval for PR 709 approval
• Request @gmelodie @richard-ramos approval PR 729

---

NEW PRs requesting review and feedback

1. Address Manager spec [link]

Drafted by Gabriel Cruz (nim-libp2p team) to resolve conflicting reachability observations from different peers (e.g. differing views of a node's IP address). Proposed behavior covers source trust, conflicting information, and configurability.

Update, Sep 9 meeting

• Gabriel requested confirmation on whether this belongs in the spec set at all; he'll take review time this week and send feedback within a day or so.
• Related work flagged by Manu by Elena at rust-libp2p, who approached the same reachability/discovery/trust problem from the identity layer (dating back to May 2025). Manu to locate and share her PR with Gabriel.
• Gabriel to consider whether part of the problem should be addressed through identity rather than only through an Address Manager.

---

Existing PRs updates

1. TLS Handshake to enable support for RFC 9849, TLS Encrypted Client Hello (also covers ECH with QUIC)

Relevant Links
#730

Update, Sep 9 meeting

• Spec is ready; Go implementation has not yet started.
• This week, the team plans to test ECH with QUIC using the Python implementation, alongside Go, before Marco begins the Go-libp2p implementation work.
• Richard shared feedback on the TCP flow. Manu to follow up with Richard on whether Nim (one of the strongest QUIC implementations) could also be used for testing.
• Active implementation targets identified: Rust, Nim, Go, and Python.

6. Topic Streams Extension addition in Gossipsub, moves topic scoped application messages to separate long lived streams [link]

Relevant Links
libp2p/test-plans#860

Update, Sep 9 meeting

• No substantive new update this meeting. Manu flagged that this may now be covered by Gabriel's SPREAD extension work (PR 726), and the two will discuss whether 729 should be closed or redirected.

Next Steps

• Coordinate with Gabriel on whether PR 729 stays open or is superseded by 726.

7. gossipsub, add SPREAD extension spec

[Spec PR] #726

Update, Sep 9 meeting

• Author Matthew has incorporated feedback from Manu, Richard, and Gabriel and posted an updated PR comment.
• PR now has two approvals and is considered close to final review.
• Gabriel to do a final check for any outstanding comments and reply to Matthew's latest comment on the thread.

Next Steps

• Final review pass, then move to merge.

8. Object Cache [link]

Background
This is a Waggle PR opened by a rust maintainer.

Update, Sep 9 meeting

• No new update surfaced in this meeting.

9. Multi Stream Select V2

Background
Marco's draft (with input from Martin Seaman and Sukun) proposing a minimal libp2p feature set so custom peer to peer stacks can be built in other languages, motivated in part by a Quic plus Multi Stream Select approach to the Lean Ethereum work.

Update, Sep 9 meeting

• Architecture and documentation are substantially developed, but discussion stalled a few months back.
• Needs renewed eyes and review before determining next direction.

10. Key set support PR [link]

Background
Adds support for additional key sets (e.g. CORS keys), tied to deterministic CBOR work and PQ client support; references IETF standard 9679.

Update, Sep 9 meeting

• Dennis previously asked a set of questions which Lidel responded to.
• Marco to follow up, or add a maintainer as collaborator, to move the PR toward a conclusion.

11. Post-Quantum Signatures [PRs #717 and #711, plus related PRs from Ste and Lidel]

Relevant Links
#717 (PKIX based infrastructure)
#711 (Marco, PKIX and PKCS8 keys)

Update, Sep 9 meeting

• Manu opened discussion on four PQ related PRs. 717 proposes PKIX based infrastructure aimed at interoperating with PQC blockchains (Ethereum's Lean roadmap, Algorand, Hedera). 711 (Marco) proposes PKIX/PKCS8 key support. Two further PRs from Ste (js-libp2p) and Lidel cover an MLDSA/multicodec level approach.
• Central open problem: a PQ client can interoperate with another PQ client, but backward compatibility breaks when a PQ client interacts with a non PQ client.
• Three candidate directions surfaced: extend the Peer ID definition itself; keep Peer ID untouched and introduce PQ support at the multicodec level; or hold off and study PQC requirements from Algorand and Hedera before deciding.
• Group consensus leaned toward extending Peer ID being high risk given how central it is as a primitive, so no design has been finalized.
• Plan going forward: pilot PQ support in the TLS module first, then extend to Noise once validated.
• Feedback so far gathered from the Ethproofs community, the Lean Roadmap community, Chainsafe, and the IPFS/Helia community.
• Feedback on 717 requested from all participants before converging on one or two approaches.

---

Spec PRs ready to merge

1. WebRTC Direct V2 [Now at candidate recommendation]

Relevant Links

• [Summary] by lidel on WebRTC-Direct + Chrome changes (specs#672 comment at WebRTC-Direct: Chrome may be removing ICE credential munging #672 (comment))
• [Spec PR Link] docs: webrtc-direct-v2 #715
• [Issue Link] WebRTC-Direct transport at risk due to Chrome changes (ICE credential munging): alignment and next steps go-libp2p#3499
• [js-libp2p PR Link] feat: webrtc-direct-v2 js-libp2p#3480
• [py-libp2p PR Link] feat(webrtc): add WebRTC transport scaffolding (spec compliance + tests) py-libp2p#1309 (comment)
• [go-libp2p Reference Link] feat(webrtc): stable /certhash across restarts go-libp2p#3512

Update, Sep 9 meeting

• PR now has three approvals.
• Manu to ask Steve in the call to complete the merge.

Next Steps

• Merge, then move to Spec Lifecycle Stage 4, Recommendation.

2. Signed Peer Records [link]

Update, Sep 9 meeting

• Fully ready for merge. Approved by Marco; feedback from Richard (notably the signed peer record section and message size discussion) and Gabriel has been received and largely resolved.
• Manu to respond to remaining points on Alex's behalf, request collaborator access to the repo, apply the remaining changes from Richard and Gabriel, and move it to final merge.

AOB

Nothing further raised.