<oembed><type>rich</type><version>1.0</version><author_name>npub18df3zgqr9zt5ah42zpd34rmq6fp7v57vvwmtk20krhrfdczp38ks5xccej</author_name><author_url>https://nostr.ae/npub18df3zgqr9zt5ah42zpd34rmq6fp7v57vvwmtk20krhrfdczp38ks5xccej</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2017-09-27&#xA;📝 Original message:A better solution is to just have the sending wallet check to see if the&#xA;address you are about to send to has been used before. If it&#39;s a fresh&#xA;address, it sends it through without any popup alert. If the address has&#xA;history going back a certain amount of time, then a popup comes up and&#xA;notifies the sender that they are sending to a non-fresh address that may&#xA;no longer be controlled by the receiver anymore.&#xA;&#xA;Also, an even better idea is to set up an &#34;address expiration service&#34;.&#xA;When you delete a wallet, you first send off an &#34;expiration notice&#34; which&#xA;is just a message (signed with the private key) saying &#34;I am about to&#xA;delete this address, here is my new address&#34;. When someone tries to send to&#xA;that address, they first consult the address expiration service, and the&#xA;service will either tell them &#34;this address is not expired, proceed&#34;, or&#xA;&#34;this address has been expired, please send to this other address&#xA;instead...&#34;. Basically like a 301 redirect, but for addresses. I don&#39;t&#xA;think address expiration should be part of the protocol.&#xA;&#xA;On Wed, Sep 27, 2017 at 10:06 AM, Peter Todd via bitcoin-dev &lt;&#xA;bitcoin-dev at lists.linuxfoundation.org&gt; wrote:&#xA;&#xA;&gt; Re-use of old addresses is a major problem, not only for privacy, but also&#xA;&gt; operationally: services like exchanges frequently have problems with users&#xA;&gt; sending funds to addresses whose private keys have been lost or stolen;&#xA;&gt; there&#xA;&gt; are multiple examples of exchanges getting hacked, with users continuing to&#xA;&gt; lose funds well after the actual hack has occured due to continuing&#xA;&gt; deposits.&#xA;&gt; This also makes it difficult operationally to rotate private keys. I&#xA;&gt; personally&#xA;&gt; have even lost funds in the past due to people sending me BTC to addresses&#xA;&gt; that&#xA;&gt; I gave them long ago for different reasons, rather than asking me for fresh&#xA;&gt; one.&#xA;&gt;&#xA;&gt; To help combat this problem, I suggest that we add a UI-level expiration&#xA;&gt; time&#xA;&gt; to the new BIP173 address format. Wallets would be expected to consider&#xA;&gt; addresses as invalid as a destination for funds after the expiration time&#xA;&gt; is&#xA;&gt; reached.&#xA;&gt;&#xA;&gt; Unfortunately, this proposal inevitably will raise a lot of UI and&#xA;&gt; terminology&#xA;&gt; questions. Notably, the entire notion of addresses is flawed from a user&#xA;&gt; point&#xA;&gt; of view: their experience with them should be more like &#34;payment codes&#34;,&#xA;&gt; with a&#xA;&gt; code being valid for payment for a short period of time; wallets should&#xA;&gt; not be&#xA;&gt; displaying addresses as actually associated with specific funds. I suspect&#xA;&gt; we&#39;ll see users thinking that an expired address risks the funds&#xA;&gt; themselves;&#xA;&gt; some thought needs to be put into terminology.&#xA;&gt;&#xA;&gt; Being just an expiration time, seconds-level resolution is unnecessary, and&#xA;&gt; may give the wrong impression. I&#39;d suggest either:&#xA;&gt;&#xA;&gt; 1) Hour resolution - 2^24 hours = 1914 years&#xA;&gt; 2) Month resolution - 2^16 months = 5458 years&#xA;&gt;&#xA;&gt; Both options have the advantage of working well at the UI level regardless&#xA;&gt; of&#xA;&gt; timezone: the former is sufficiently short that UI&#39;s can simply display an&#xA;&gt; &#34;exact&#34; time (though note different leap second interpretations), while the&#xA;&gt; latter is long enough that rounding off to the nearest day in the local&#xA;&gt; timezone is fine.&#xA;&gt;&#xA;&gt; Supporting hour-level (or just seconds) precision has the advantage of&#xA;&gt; making&#xA;&gt; it easy for services like exchanges to use addresses with relatively short&#xA;&gt; validity periods, to reduce the risks of losses after a hack. Also, using&#xA;&gt; at&#xA;&gt; least hour-level ensures we don&#39;t have any year 2038 problems.&#xA;&gt;&#xA;&gt; Thoughts?&#xA;&gt;&#xA;&gt; --&#xA;&gt; https://petertodd.org &#39;peter&#39;[:-1]@petertodd.org&#xA;&gt;&#xA;&gt; _______________________________________________&#xA;&gt; bitcoin-dev mailing list&#xA;&gt; bitcoin-dev at lists.linuxfoundation.org&#xA;&gt; https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev&#xA;&gt;&#xA;&gt;&#xA;&#xA;&#xA;-- &#xA;Chris Priest&#xA;786-531-5938&#xA;-------------- next part --------------&#xA;An HTML attachment was scrubbed...&#xA;URL: &lt;http://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20170927/e853137e/attachment.html&gt;</html></oembed>