Subject: Re: [bitcoin-dev] Moving towards user activated soft fork activation

From: Gareth Williams <[email-masked]>
Date: Tue, 07 Mar 2017 10:23:47 +1100

What you're describing is a hashpower activated soft fork to censor transactions, in response to a user activated soft fork that the majority of hashpower disagrees with.

It is always possible for a majority of hashpower to censor transactions they disagree with. Users may view that as an attack, and can always respond with a POW hard fork. 

Bitcoin only works if the majority of hashpower is not hostile to the users.

On 6 March 2017 9:29:35 PM AEDT, Edmund Edgar via bitcoin-dev <[email-masked]> wrote:
>On 6 March 2017 at 18:18, David Vorick via bitcoin-dev
><[email-masked]> wrote:
>> User activated soft forks, or perhaps more accurately called
>'economically
>> forced soft forks' are a tool to use if the miners are in clear
>opposition
>> to the broader economy.
>
>I don't think they work for that, at least not for new features,
>because miners will presumably just head the whole thing off by
>orphaning the whole class of non-standard transactions that are the
>subject of the fork. In the SegWit case, they'd just orphan anything
>that looks like a SegWit transaction, valid or not. That way they
>don't need to worry about ending up on the wrong side of the upgrade,
>because no transaction affected by the proposed rule change will ever
>get into the longest chain. Rational node operators (particularly
>exchanges) will likely also adopt their stricter rule change, since
>they know any chain that breaks it will end up being orphaned, so you
>don't want to act on a payment that you see confirmed in it. So then
>you're back where you started, except that your soft-fork is now a
>de-facto hard-fork, because you have to undo the new, stricter rule
>that the miners introduced to head off your shenannigans.
>
>Where they're interesting is where you can do something meaningful by
>forcing some transactions through on a once-off basis. For example, if
>the Chinese government identified an address belonging to Uighur
>separatists and leaned on Chinese miners to prevent anything from that
>address confirming, it might be interesting for users to say, "If
>these utxos are not spent by block X, your block is invalid".
>
>They might also be interesting for feature upgrades in a world where
>mining is radically decentralized and upgrades are fighting against
>inertia rather than opposition, but sadly that's not the world we
>currently live in.