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Date: Wed, 30 Oct 2013 10:13:49 -0700
Message-ID: <CAAS2fgSAtjB0EMgBG0AphWADxCwLhutGFJEx74mLC=zCEY3QAA@mail.gmail.com>
From: Gregory Maxwell <gmaxwell@gmail.com>
To: Mike Hearn <mike@plan99.net>
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Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>,
	kjj <bitcoin-devel@jerviss.org>
Subject: Re: [Bitcoin-development] Feedback requested: "reject" p2p message
Precedence: list

On Sun, Oct 27, 2013 at 7:32 AM, Mike Hearn <mike@plan99.net> wrote:
> I'm really looking forward to this. Currently bitcoinj gets a small but
> steady stream of bug reports of the form "my transaction did not propagate".
> It's flaky because the library picks one peer to send the transaction to,
> and then watches it propagate across the network. But if that selected peer
> refuses the tx for whatever reason, that propagation never comes, and

Actually, we'll probably need to explicitly document that a failure to
reject is by no means a promise to forward.

If a node is using priority queued rate limiting for its relaying then
it might "accept" a transaction from you, but have it fall out of its
memory pool (due to higher priority txn arriving, or getting
restarted, etc.) before it ever gets a chance to send it on to any
other peers.

Finding out that it rejected is still useful information, but even
assuming all nodes are honest and well behaved I don't think you could
count on its absence to be sure of forwarding.