Author: David A. Harding 2020-01-10 18:30:07
Published on: 2020-01-10T18:30:07+00:00
In an email thread, Bitcoin developer ZmnSCPxj discussed the issue of `nSequence` relative-locktime transactions that protect the security of channel mechanism. Unilateral close may occur far in the future, making any non-0 `nLockTime` obsolete. However, there is no problem as long as there is no conflict created by using both relative and absolute locktimes in the same transaction. Multiple versions of a commitment transaction may be signed, each with different nLockTimes but all other parts of the transaction the same. To deal with the issue, Bitcoin Core would have to toss a coin and use a relative-locktime `nSequence` equal to the confirmations of the output being spent and an `nLockTime` of 0 if it lands tails. Commitment transactions for current two-party Lightning Network (LN) have at least two outputs; the chance of both outputs being spent with an nLockTime of 0 is 25%. This bias can be combined with other indicators to identify LN transactions for analytics or censorship.
Updated on: 2023-06-02T22:15:54.781467+00:00