For simplicity, assume total network hashpower is constant. Also, assume the 
soft fork activates at the beginning of a retarget period.

At the moment the soft fork activates, the effective difficulty is increased 
(by adding a second independent PoW check that must also be satisfied) which 
means more hashes on average (and proportionally more time) are required to 
find a block. At the end of the retarget period,  the difficulty is lowered so 
that if the second PoW difficulty were to be kept constant the block interval 
would again average 10 mins.

If we were to keep the second PoW difficulty constant, we would restore the 
same total PoW-to-time-unit ratio and the retarget difficulty would stabilize 
again so each block would once more require the same number of hashes (and same 
amount of time) on average as before.

But we don't keep the second PoW difficulty constant - we increase it so once 
again more hashes on average are required to find a block by the same 
proportion as before. And we keep doing this.

Now, the assumption that hashpower is constant is obviously unrealistic. If 
this is your bone of contention, then yes, I agree my model is overly 
simplistic.

My larger point was to explore the extent of what's possible with only a soft 
fork - and we can actually go pretty far and even compensate for these economic 
shifts by increasing block size and rewards. The whole thing is clearly a huge 
mess - and I wouldn't recommend actually doing it.



On December 26, 2015 7:33:53 AM PST, "Jorge Timón" <jti...@jtimon.cc> wrote:
>On Dec 26, 2015 9:24 AM, "Eric Lombrozo via bitcoin-dev" <
>bitcoin-dev@lists.linuxfoundation.org> wrote:
>
>> Unfortunately, this also means longer confirmation times, lower
>throughput, and lower miner revenue. Note, however, that confirmations
>would (on average) represent more PoW, so fewer confirmations would be
>required to achieve the same level of security.
>>
>
>I'm not sure I understand this. If mining revenue per unit of time
>drops,
>total pow per unit of time should also drop. Even if the inter-block
>time
>is increased, it's not clear to me that the pow per block would
>necessarily
>be higher.
>What am I missing?
_______________________________________________
bitcoin-dev mailing list
bitcoin-dev@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev

Reply via email to