MIME-Version: 1.0
In-Reply-To: <CADJgMzsvAfJnW1DDD6t3qkBcQRLb4HMqG27k51LhXJqxC6-z4g@mail.gmail.com>
References: <20150819055036.GA19595@muck>
	<CAOG=w-unJ+xnWFgiBO3jmgj4Q72ZH6-LOn08TwUF58trc-_WWg@mail.gmail.com>
	<CABm2gDpBLKxKbHyWocOuyfO1VZ45yM7U1t+zVL_13LP9veXmcA@mail.gmail.com>
	<CADJgMztmgUzy70sJ+_Xj-OFe-kvEi6eSAYoGTb4yg-yGQ9u1dw@mail.gmail.com>
	<CABm2gDqRycGY2diXoTvL+d5JE0EgccgGdiQdgWj8c_9SMokJEw@mail.gmail.com>
	<CADJgMztysqVya1nnRatyav5rqcpEZ81CmXxW0ZqwJoLN7W2=hg@mail.gmail.com>
	<CAE-z3OVAJcnFn21F9QTGCf=NZrLQ9hAtj_tqSCboQGCfFSvq=Q@mail.gmail.com>
	<CADJgMzsvAfJnW1DDD6t3qkBcQRLb4HMqG27k51LhXJqxC6-z4g@mail.gmail.com>
Date: Wed, 19 Aug 2015 19:17:15 +0100
Message-ID: <CAE-z3OV=sEd18JY1raVf5j9XTnEZ+vovkuQw57V9UoSXh6Affw@mail.gmail.com>
From: Tier Nolan <tier.nolan@gmail.com>
To: Btc Drak <btcdrak@gmail.com>
Content-Type: multipart/alternative; boundary=001a114661985ce5bc051dae0b0e
Cc: Bitcoin Dev <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] CLTV/CSV/etc. deployment considerations due to
 XT/Not-BitcoinXT miners
Precedence: list

--001a114661985ce5bc051dae0b0e
Content-Type: text/plain; charset=UTF-8

On Wed, Aug 19, 2015 at 6:25 PM, Btc Drak <btcdrak@gmail.com> wrote:

> In our case for Bitcoin Core, option 2 we use nVersion=8, apply a
> bitmask of 0xdffffff8 thus:
>
>     if ((block.nVersion & ~0x20000007) >= 4 &&
> CBlockIndex::IsSuperMajority(...)) { //...}
>
> With nVersion=8, but using comparison >=4 allows us to recover the
> bit later, assuming we want it (otherwise we use version >=8).
>

That is the 75% "activation" rule portion?  The 95% rule has to apply to
all blocks.

The supermajority applies to unmasked blocks?

I think you want it so that a sequence of blocks with version 8 can be
followed by version 4 blocks?

If 950 of the last 1000 blocks have bit 0x08 set, then reject any block
with a version less than 4.

This means transitioning to the version bits BIP just requires dropping the
version back to 4 and adding a rule enforcing the BIPs for version 4 and
higher blocks.

This would be part of the version bits BIP enforcement.

--001a114661985ce5bc051dae0b0e
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr"><div class=3D"gmail_extra"><div class=3D"gmail_quote">On W=
ed, Aug 19, 2015 at 6:25 PM, Btc Drak <span dir=3D"ltr">&lt;<a href=3D"mail=
to:btcdrak@gmail.com" target=3D"_blank">btcdrak@gmail.com</a>&gt;</span> wr=
ote:<br><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border=
-left:1px #ccc solid;padding-left:1ex">
In our case for Bitcoin Core, option 2 we use nVersion=3D8, apply a<br>
bitmask of 0xdffffff8 thus:<br>
<br>
=C2=A0 =C2=A0 if ((block.nVersion &amp; ~0x20000007) &gt;=3D 4 &amp;&amp;<b=
r>
CBlockIndex::IsSuperMajority(...)) { //...}<br>
<br>
With nVersion=3D8, but using comparison &gt;=3D4 allows us to recover the<b=
r>
bit later, assuming we want it (otherwise we use version &gt;=3D8).<br></bl=
ockquote><div><br></div><div>That is the 75% &quot;activation&quot; rule po=
rtion?=C2=A0 The 95% rule has to apply to all blocks.<br></div><div><br></d=
iv><div>The supermajority applies to unmasked blocks?<br><br></div><div>I t=
hink you want it so that a sequence of blocks with version 8 can be followe=
d by version 4 blocks?<br><br></div><div>If 950 of the last 1000 blocks hav=
e bit 0x08 set, then reject any block with a version less than 4.<br><br></=
div><div>This means transitioning to the version bits BIP just requires dro=
pping the version back to 4 and adding a rule enforcing the BIPs for versio=
n 4 and higher blocks.<br><br></div><div>This would be part of the version =
bits BIP enforcement.<br></div></div></div></div>

--001a114661985ce5bc051dae0b0e--