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From: Braydon Fuller <braydon@purse.io>
To: Tier Nolan <tier.nolan@gmail.com>,
	Bitcoin Protocol Discussion
	<bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Chain width expansion
Date: Wed, 16 Oct 2019 12:07:25 -0700	[thread overview]
Message-ID: <8d1e2696-0245-638a-61fa-8f79845136d5@purse.io> (raw)
In-Reply-To: <CAE-z3OVqU5n8H9vKj9Pn7k80guMTsxt_CkN9qwpfCK8HB4PDgQ@mail.gmail.com>

On 10/12/19 1:46 PM, Tier Nolan via bitcoin-dev wrote:

> On Sat, Oct 12, 2019 at 6:56 PM Joachim Strömbergson <joachimstr@protonmail.com> wrote:
>> On different note, one of the problems that I haven't seen mentioned here
>> yet is the timewarp attack. It is relevant to some of the proposed
>> solutions. It should be possible, IIRC, for a malicious node to generate
>> much longer chain with superslow timestamp increase (~5 blocks in 1 second)
>> without increasing difficulty (i.e. staying at min. diff.). This could
>> produce chain that is ~2500 times longer than main chain without having
>> multiple branches.
>>
> [..]
>
> The timewarp bug can be fixed by a basic soft fork.  You just need to limit
> the maximum difference between the timestamp for the first header in a
> period and the last header in the previous period.

Yeah, that makes sense as it corrects the off-by-one error. I think this
solution has been included in a draft proposal "The Great Consensus
Cleanup". It would need to be effective for not only the main chain but
also for any future forked chain.




  reply	other threads:[~2019-10-16 19:07 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-04  0:38 [bitcoin-dev] Chain width expansion Braydon Fuller
2019-10-04  8:20 ` David A. Harding
2019-10-04 19:51   ` Braydon Fuller
2019-10-11 21:24   ` Braydon Fuller
2019-10-04 23:31 ` Tier Nolan
2019-10-10 16:16   ` Braydon Fuller
2019-10-12 16:27     ` Tier Nolan
2019-10-12 17:56       ` Joachim Strömbergson
2019-10-12 20:46         ` Tier Nolan
2019-10-16 19:07           ` Braydon Fuller [this message]
2019-10-15  0:42         ` Braydon Fuller
2019-10-15  7:20           ` Joachim Strömbergson
2019-10-15  8:12             ` Braydon Fuller
2019-10-15 15:50               ` Joachim Strömbergson
2019-10-16 19:25                 ` Braydon Fuller
2019-10-15 18:30           ` Tier Nolan
2019-10-15  0:38       ` Braydon Fuller

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