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Date: Wed, 25 Mar 2015 16:34:36 +0000
Message-ID: <CAAS2fgRzskGcHjEhJLnyu-VMTR49i-Wo9TbOOqkHqEasxuO71A@mail.gmail.com>
From: Gregory Maxwell <gmaxwell@gmail.com>
To: Tom Harding <tomh@thinlink.com>
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Cc: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Address Expiration to Prevent Reuse
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On Wed, Mar 25, 2015 at 1:57 AM, Tom Harding <tomh@thinlink.com> wrote:
> The idea of limited-lifetime addresses was discussed on 2014-07-15 in
>
> http://thread.gmane.org/gmane.comp.bitcoin.devel/5837
>
> It appears that a limited-lifetime address, such as the fanciful
>
> address = 4HB5ld0FzFVj8ALj6mfBsbifRoD4miY36v_349366

Assuming the sender is not an uncooperative idiot, you can simply
include expiration information and the sender can refuse to send after
that time.

If the sender is an uncooperative idiot, they can always change your
target and send anyways.

This would seem to work nearly as well as the non-reorg safe network
impacting version, and yet has no cost beyond the extra size is
communicating the limit.

> Block containing tx invalid if a prior confirmed tx has paid address

Requires a unprunable verification state.