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Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Squashing redundant tx data in blocks on
the wire
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On Thu, Jul 31, 2014 at 3:27 PM, Kaz Wesley <keziahw@gmail.com> wrote:
>> the FEC still lets you fill in the missing transactions without knowing =
in advance all that will be missing.
>
> I don't see why we need to solve that problem, since the protocol
> already involves exchanging the information necessary to determine
> (with some false positives) what a peer is missing, and needs to
> continue doing so regardless of how blocks are transmitted.
False positives, and if you have more than one peer=E2=80=94 false negative=
s.
(or a rule for what you must keep which is conservative in order to
avoid creating huge storage requirements=E2=80=94 but then also has false
negatives).
> As far as I can tell, channel memory sparseblocks achieve most of the
> possible bandwidth savings, and when FEC-based mempool synchronization
> is implemented its benefits can be applied to the sparseblocks by
> resetting the channel memory to the mutual mempool state each time
> mempool differences are exchanged. Am I missing a benefit to doing FEC
> at block forwarding time that can't be realized by FEC-based mempool
> synchronization, implemented separately from channel-memory based
> index-coding?
Yes, minimizing latency in the face of multiple peers.
Otherwise no. And certantly no reason to to implement something simple firs=
t.
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