[Cryptography] Best Internet crypto clock ?

Henry Baker hbaker1 at pipeline.com
Wed Oct 8 12:16:42 EDT 2014

At 08:57 AM 10/8/2014, Bear wrote:
>I have to point out here that there is absolutely nothing in the Bitcoin
>protocol that prevents servers who solve a block from misreporting 
>the time.
>In fact, it has been a strategy in the past for parallelizing the
>hashing. When the portion of the nonce that people could adjust 
>seeking a winning hash was exceeded by hardware capacity, the 
>time field was incremented even though the mentioned time had 
>not yet arrived, and the search started over.  Because that was 
>faster than rearranging the transactions to form a different 
>base for hashing, I guess.  
>Anyway, the time reported in bitcoin blocks is approximate, and 
>historically not even monotonically increasing.  It is testimony
>that the Bitcoin network accepted the server's claim of what 
>time it was, so probably, usually, within ten minutes of  the 
>real time.  But it does not establish any precise notion of time. 

For most purposes, the time priority relative to some other events
_not under any one organization's control_ is more important than
some nominal time value.  After all, almost all digital devices
these days include some form of a clock; the problem is, we can't
believe these clock values unless they are "laced up" with external
events in such a way that the clock values can't have been spoofed
by very much.

So no, the nominal clock value in the Bitcoin blockchain is no
more trustworthy than my computer's own clock.

That having been said, a proper Internet crypto clock _would_
make a much better attempt to correspond with real GMT, and
_would_ attempt to produce a strict monotonically increasing
series of nominal clock values, in addition to its crypto
hash "ticks".

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