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Date: Tue, 15 Jul 2014 18:26:15 +0200
Message-ID: <CANEZrP1n+oK1_OH2njmYy0S9J1qLb9MqHF2HY6NONovwB9bC0A@mail.gmail.com>
From: Mike Hearn <mike@plan99.net>
To: Jeff Garzik <jgarzik@bitpay.com>
Content-Type: multipart/alternative; boundary=089e0158ac78d82a7d04fe3ddd91
Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Bitcoin address TTL & key expiration?
Precedence: list

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>
> Actually, and this is key, there _are_ reasons why deposits might not
> be able to use PaymentRequests.  Payments happen even when
> wallets/computers are offline.
>

I don't understand this point. It's the *sender* that is parsing the
PaymentRequest and following the instructions. By definition the sender
must be online. A computer that is switched off cannot sign a transaction
at all.


> If you have negotiated HD wallet details, you can use a new address
> every time, as mentioned.


Yes, and an extension to BIP 70 to allow for this (or stealth addresses or
whatever) has been discussed several times.

This thread started by proposing (I think) an expiry time for addresses.
BIP70 satisfies this use case, I think we all agree on that. Now for cases
where someone can't use BIP70 for whatever reason, or it's suboptimal,
absolutely we should design extensions to fix that.

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<div dir=3D"ltr"><div class=3D"gmail_extra"><div class=3D"gmail_quote"><blo=
ckquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #c=
cc solid;padding-left:1ex"><div class=3D"">Actually, and this is key, there=
 _are_ reasons why deposits might not<br>
</div>
be able to use PaymentRequests. =C2=A0Payments happen even when<br>
wallets/computers are offline.<br></blockquote><div><br></div><div>I don=
9;t understand this point. It&#39;s the <i>sender</i>=C2=A0that is parsing =
the PaymentRequest and following the instructions. By definition the sender=
 must be online. A computer that is switched off cannot sign a transaction =
at all.</div>
<div>=C2=A0</div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8=
ex;border-left:1px #ccc solid;padding-left:1ex">If you have negotiated HD w=
allet details, you can use a new address<br>
every time, as mentioned.</blockquote><div><br></div><div>Yes, and an exten=
sion to BIP 70 to allow for this (or stealth addresses or whatever) has bee=
n discussed several times.</div><div><br></div><div>This thread started by =
proposing (I think) an expiry time for addresses. BIP70 satisfies this use =
case, I think we all agree on that. Now for cases where someone can&#39;t u=
se BIP70 for whatever reason, or it&#39;s suboptimal, absolutely we should =
design extensions to fix that.</div>
</div></div></div>

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