[feature]: Spec. change: We should consider a channel closed only after 72 blocks passed

[ziggie1984]

we increase the time delay when we consider a channel as closed to 72 blocks. See the Spec. PR for more infos. The reason for this increase is the new splicing feature. The new time delay assures that a new channel_announcment has time to propagate for the new spliced channel.

lightning/bolts#1270

[yyforyongyu]

This will only be relevant when splicing is implemented in lnd?

[ziggie1984]

No I don't think so because other implementations already splice channels and sent updated gossip for those channels. So it is also important that we adhere to these new gossip rules of the spec. (also Matt from LDK and @morehouse confirmed this yesterday during the spec. meeting) that we should follow these new rules.

[ziggie1984]

Thinking about it twice I need to investigate if we really need to implement this before we have splicing, you raising a valid point, thank you.

[ziggie1984]

T-Bast explained it nicely here: lightning/bolts#1270 (comment)

So the general problem is the following, if we do not implement the delay we punish node-runners doing splices in our routing algorithm. Because when the spliced channel is announced we would first check if the confirmation depth is 6 blocks, so a spliced channel would have a usage delay of 6 blocks, and moreover the old history in our mission control would also not be remembered and we would disadvantage those channels.

can you implement this in LND 21 @saubyk ?

[Roasbeef]

Tracked here: #7865.

We can update it to 72.