Bitcoin Forum

Bitcoin => Development & Technical Discussion => Topic started by: Brennus101 on January 04, 2018, 08:43:02 AM



Title: Question about locktime
Post by: Brennus101 on January 04, 2018, 08:43:02 AM
According to my understanding, if the the locktime field has a value lower than 500 million, it is interpreted as specifying the lowest block height at which the transaction will be made, and if it is higher than 500 million, it represents the earliest point in time, counted in seconds from Jan 1 1970 (Epoch Time), that the transaction will be made.

What are the reasons behind the choice of 500 million? There are more than 31 million second in a year, so when Bitcoin was launched on Jan 3 2009, the Epoch Time must have been larger than 39*31 million = 1209 million. In fact, the Epoch Time on Jan 3 2009 at 0 am is around 1230 million. Hence it seems like you could have picked the limit 1200 million rather than 500 million.

I understand that 500 million blocks is quite sufficient, since you can specify block heights roughly 9500 years in the future, assuming 6 blocks per hour. Still, given what was pointed out above, 500 million seems rather arbitrary.

Thoughts?


Title: Re: Question about locktime
Post by: achow101 on January 05, 2018, 01:23:07 AM
It's an arbitrary large number.


Title: Re: Question about locktime
Post by: Brennus101 on January 05, 2018, 10:21:58 PM
Thanks!