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From: Tom Zander <tomz@freedommail.ch>
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Date: Tue, 11 Apr 2017 09:59:33 +0200
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Subject: Re: [bitcoin-dev] A Small Modification to Segwit
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The version field is still needed to actually allow future block version=20
upgrades. We would cut off our road forward if that were to be blocked.


On Friday, 7 April 2017 22:06:39 CEST Jimmy Song via bitcoin-dev wrote:
> Currently, the version bits (currently 4 bytes, or 32 bits) in the header
> are used for BIP9 signaling. We change the version bits to a nonce-space
> so the miners can use it for overt ASICBoost. The 32-bits are now moved
> over to the Coinbase transaction as part of the witness commitment. The
> witness commitment goes from 38 bytes to 42 bytes, with the last 4 bytes
> being used as the version bits in the block header previously. The
> witness commitment becomes required as per Gregory Maxwell=E2=80=99s prop=
osal.
> Reasoning


=2D-=20
Tom Zander
Blog: https://zander.github.io
Vlog: https://vimeo.com/channels/tomscryptochannel