Message-ID: <52EA343E.4010208@borboggle.com>
Date: Thu, 30 Jan 2014 18:15:10 +0700
From: Chuck <chuck+bitcoindev@borboggle.com>
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64;
	rv:24.0) Gecko/20100101 Thunderbird/24.2.0
MIME-Version: 1.0
To: Mike Hearn <mike@plan99.net>
References: <52E9E787.8080304@borboggle.com>
	<CANEZrP0soR0xRqW=vsKaL__HRuWstA5vW=6_JkGZm=8wkm8Q3g@mail.gmail.com>
In-Reply-To: <CANEZrP0soR0xRqW=vsKaL__HRuWstA5vW=6_JkGZm=8wkm8Q3g@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Cc: Bitcoin-Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] BIP70 message delivery reliability
Precedence: list

Hi Mike.  Thanks for replying.

On 1/30/2014 5:49 PM, Mike Hearn wrote:
> Both Bitcoin Core and bitcoinj are about to ship with the protocol 
> as-is, so any changes from this point on have to be backwards compatible.
Then I think it's critically important to talk about failure situations 
now, rather than trying to patch on solutions later; it's going to be 
very hard to wedge/"hack" in fixes for potential problems when they 
could be addressed now with minor changes.
> Let's get some practical experience with what we've got so far. We can 
> evolve PaymentRequest/Payment/PaymentACK in the right direction with 
> backwards compatible upgrades, I am hoping.
I think what I'm trying to discuss or find out here is whether the 
current PP description is defunct or incomplete in some manner, thus 
making any experience we gain from the current implementation moot.

It seems the largest hole in the implementation is delivery of the 
Payment message, but I'm happy to accept that maybe I'm just missing 
something.  A malicious merchant could claim he never received the 
Payment message, or a faulty network connection could cause the message 
to never be delivered. In arbitration the merchant could argue the 
transactions seen on the network were insufficient.

To me, this could be a problem.

Cheers,

Chuck