Lightning Specification Meeting 2023/06/19

[t-bast]

The meeting will take place on Monday 2023/06/19 at 8pm UTC (5:30am Adelaide time) on Libera Chat IRC #lightning-dev. It is open to the public.

A video link is available for higher bandwidth communication: https://meet.jit.si/Lightning-Spec-Meeting

Recently Updated Proposals / Seeking Review

This section contains changes that have been opened or updated recently and need feedback from the meeting participants.

• Bolt 8 chaining keys clarification BOLT 8: make it clear that there are *two* chaining keys. #1079
• Correct final CLTV for blinded paths: Correct final_cltv handling in blinded paths #1066 and Clarify final cltv expiry computation in route blinding #1069
• Harmonize max cltv_expiry across implementations BOLT4: Specify max HTLC nLocktime for expiry_too_far #1086
• Fat errors Attributable errors (feature 36/37) #1044
• Onion messages BOLT 7: Onion message support (features 38/39) #759
• Offers Offers #798
• Add dust exposure threshold Add a max_dust_htlc_exposure_msat #919
• Taproot extension-bolt: simple taproot channels (feature 80/81) #995
• Taproot gossip extension-bolt: taproot gossip (features 32/33) #1059
• Quiescence BOLT 2: quiescence protocol (feature 34/35) option_quiesce #869
• Splicing Splice draft (feature 62/63) #863
• Clarify channel_reestablish requirements Clarify channel_reestablish requirements #1049 or Rework channel_reestablish requirements #1051

Stale Proposals

This section contains pending changes that may not need feedback from the meeting participants, unless someone explicitly asks for it during the meeting. These changes are usually waiting for implementation work to happen to drive more feedback.

• Inbound fees Inbound routing fees blips#18 and Add a bLIP for backwards-compatible inbound fees blips#22
• Closing fee range turn-based protocol option_closing_rejected: turn-based fee_range coop close (feature 60/61) #1016
• Update static channel parameters zzz-extension-bolt: dynamic commitments #1026
• Liquidity ads option_will_fund: liquidity ads #878
• Sign commitments at various feerates Add option to sign commitments at various feerates (FEAT 32/33) #1036

Waiting for interop

This section contains changes that have been conceptually ACKed and are waiting for at least two implementations to fully interoperate.
They most likely don't need to be covered during the meeting, unless someone asks for updates.

• Dual funding interactive-tx: Add dual-funding flow, using the interactive tx protocol (feature 28/29) #851
• Don't force close until error is received after channel_reestablish Nodes shouldn't publish their commitment when receiving outdated channel_reestablish #934
• Websocket transport websocket address type: allow transport over RFC6455 #891 or Websocket address type: attempt 2 #1068

Long Term Updates

This section contains long-term changes that need review, but require a substantial implementation effort.

• Channel jamming draft: Staking Credentials token issuance/redemption #1043 draft: Upfront Fees to Mitigate Channel Jamming #1052 draft: HTLC Endorsement to Mitigate Channel Jamming #1071
• Pinning attacks as related to splicing / dynamic commitments: https://lists.linuxfoundation.org/pipermail/lightning-dev/2022-August/003665.html
• Simplified commitment Feature 106/107: option_simplified_update. #867
• Peer storage backup Peer backup storage (feature 40/41/42/43) #881
• Hold htlcs before forwarding Add the ability to hold HTLCs before forwarding (FEAT 52/53) #989
• Trampoline routing Trampoline Routing (2021 edition) (Feature 56/57) #829 and Trampoline onion format (Feature 56/57) #836
• Anonymous gossip
• lnprototest (https://github.com/rustyrussell/lnprototest)

[joostjager]

For attributable errors, the idea came up to reduce the number of bits in the hmacs to make the failure message smaller: lightningnetwork/lightning-onion#60 (review)

Interested to hear what people think of this.

[carlaKC]

I'd like to chat about a loose structure for the upcoming summit based on interest in various topics.

[carlaKC]

Finally catching up on transcripts! bitcointranscripts/bitcointranscripts#257

[Roasbeef]

My unofficial spec meeting topic study guide based on the now abandoned daily split: https://docs.google.com/document/d/1tU9AqbCWf_rdl7gJAWN18oDFhTk_yQt8mEb3vz_F8Ls/edit?usp=sharing