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From: Matt Whitlock <bip@mattwhitlock.name>
To: Aaron Voisine <voisine@gmail.com>
Cc: bitcoin-development@lists.sourceforge.net
Subject: Re: [Bitcoin-development] SPV clients and relaying double spends
Date: Thu, 25 Sep 2014 22:07:28 -0400	[thread overview]
Message-ID: <1447373.AzvO89eGJS@crushinator> (raw)
In-Reply-To: <CACq0ZD4Ki=7Tba_2UhmuH-dPCbOnfXrJRcLPc+fP6Uur4FpG_A@mail.gmail.com>

What's to stop an attacker from broadcasting millions of spends of the same output(s) and overwhelming nodes with slower connections? Might it be a better strategy not to relay the actual transactions (after the first) but rather only propagate (once) some kind of double-spend alert?


On Thursday, 25 September 2014, at 7:02 pm, Aaron Voisine wrote:
> There was some discussion of having nodes relay double-spends in order
> to alert the network about double spend attempts.
> 
> A lot more users will be using SPV wallets in the future, and one of
> the techniques SPV clients use to judge how likely a transaction is to
> be confirmed is if it propagates across the network. I wonder if and
> when double-spend relaying is introduced, if nodes should also send
> BIP61 reject messages or something along those lines to indicate which
> transactions those nodes believe to be invalid, but are relaying
> anyway.
> 
> This would be subject to sybil attacks, as is monitoring propagation,
> however it does still increase the cost of performing a 0 confirmation
> double spend attack on an SPV client above just relaying double-spends
> without indicating if a node believes the transaction to be valid.
> 
> Aaron Voisine
> breadwallet.com




  reply	other threads:[~2014-09-26  2:21 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-09-26  2:02 [Bitcoin-development] SPV clients and relaying double spends Aaron Voisine
2014-09-26  2:07 ` Matt Whitlock [this message]
2014-09-26  2:12   ` Aaron Voisine
2014-09-26  2:16     ` Matt Whitlock
2014-09-26  2:37       ` Aaron Voisine
2014-09-26  3:34         ` Christophe Biocca
2014-09-28  2:55         ` Tom Harding
2014-09-28  5:15           ` [Bitcoin-development] replace-by-fee v0.9.3 release Peter Todd
2014-09-28 17:03             ` Luke Dashjr
2014-09-26 16:27       ` [Bitcoin-development] SPV clients and relaying double spends s7r

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