From: Gregory Maxwell <gmaxwell@gmail•com>
To: Mike Hearn <mike@plan99•net>
Cc: Bitcoin Dev <bitcoin-development@lists•sourceforge.net>
Subject: Re: [Bitcoin-development] Draft BIP for Bloom filtering
Date: Thu, 25 Oct 2012 12:56:39 -0400 [thread overview]
Message-ID: <CAAS2fgScydOWz_eqnhWxQNVUOtzvSBwkj7tttP3_DLdW+=3CTQ@mail.gmail.com> (raw)
In-Reply-To: <CANEZrP0XALwBFJyZTzYd5xBp4MRrjv0s_y2tOXbO7UgjWF2HzA@mail.gmail.com>
On Wed, Oct 24, 2012 at 11:56 AM, Mike Hearn <mike@plan99•net> wrote:
> I've written a draft BIP describing the bloom filtering protocol
> extension developed by myself and Matt.
>
> https://en.bitcoin.it/wiki/BIP_0037
Thanks for taking the time to write this up.
I still don't understand what purpose the apparently gratuitous
inefficiency of constantly resending common tree fragments. There are
many points of complexity in this protocol— handling premature
disconnections without missing blocks, the actual implementation of
the hash functions for the filter, validation of the hash tree, etc.
Presumably these components will just get implemented a few times in
some carefully constructed library code, so I don't see an
implementation complexity argument here— except the fact that it isn't
what Matt has implemented so far.
The current design can cause massive overhead compared to pulling an
unfiltered block should a filter be somewhat overboard and also makes
this filtering useless for applications which would select a small but
not tiny subset of the transactions (e.g. 10%).
Also, it's not mentioned in the page— but the hash function used is
not cryptographically strong, so what prevents a complexity (well,
bandwidth in this case) attack? someone could start using txids and
txouts that collide with the maximum number of other existing txouts
in order to waste bandwidth for people. Is this avenue of attack not
a concern?
next prev parent reply other threads:[~2012-10-25 16:56 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-24 15:56 Mike Hearn
2012-10-24 16:22 ` Pieter Wuille
2012-10-24 16:35 ` Mike Hearn
2012-10-24 17:11 ` Pieter Wuille
2012-10-24 18:54 ` Gavin Andresen
2012-10-24 19:00 ` Matt Corallo
2012-10-24 19:10 ` Mike Hearn
2012-10-24 20:29 ` Gavin Andresen
2012-10-24 20:58 ` Mike Hearn
2012-10-24 21:55 ` Jeff Garzik
2012-10-25 16:56 ` Gregory Maxwell [this message]
2012-10-25 17:01 ` Gregory Maxwell
2012-10-26 14:01 ` Mike Hearn
2012-10-26 14:17 ` Gregory Maxwell
2012-10-26 14:21 ` Mike Hearn
2012-10-26 14:34 ` Gregory Maxwell
2012-11-06 19:14 ` Pieter Wuille
2012-11-21 15:15 ` Pieter Wuille
2012-11-21 18:38 ` Matt Corallo
2012-11-27 21:10 ` Pieter Wuille
2013-01-10 15:21 ` Mike Hearn
2013-01-11 3:59 ` Matt Corallo
2013-01-11 5:02 ` Jeff Garzik
2013-01-11 14:11 ` Mike Hearn
2013-01-11 14:13 ` Mike Hearn
2013-01-16 10:43 ` Mike Hearn
2013-01-16 15:00 ` Matt Corallo
2013-01-18 16:38 ` Mike Hearn
2013-01-19 9:51 ` Andreas Schildbach
2013-01-30 11:09 ` Mike Hearn
2013-01-30 11:13 ` Mike Hearn
2013-02-06 16:33 ` Mike Hearn
2013-02-06 16:45 ` Gregory Maxwell
2013-02-20 12:44 ` Mike Hearn
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CAAS2fgScydOWz_eqnhWxQNVUOtzvSBwkj7tttP3_DLdW+=3CTQ@mail.gmail.com' \
--to=gmaxwell@gmail$(echo .)com \
--cc=bitcoin-development@lists$(echo .)sourceforge.net \
--cc=mike@plan99$(echo .)net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox