<oembed><type>rich</type><version>1.0</version><author_name>npub1trckpcxmceskq4cykxgwxm63n8ugrjrpu5mk83c90e4upsf7d9gqf0f95j</author_name><author_url>https://nostr.ae/npub1trckpcxmceskq4cykxgwxm63n8ugrjrpu5mk83c90e4upsf7d9gqf0f95j</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2015-02-05&#xA;📝 Original message:Personally I like the simplicity of tapping two phones together to&#xA;make payment - it should be quicker and easier than scanning QR codes&#xA;and it&#39;s a trust model that&#39;s hard to misunderstand.&#xA;&#xA;Is NFC good enough for that?  I fear even with NFC it is possible to&#xA;produce a device with longer range than one would expect.  What&#xA;happened to the idea of tapping two devices together and then&#xA;comparing the timing of the tap (as detected by the phones&#39;&#xA;accelerometers) to make spoofing a transaction harder?  I remember&#xA;hearing about that years ago - is that still a thing?&#xA;&#xA;roy&#xA;&#xA;On Thu, Feb 05, 2015 at 02:10:51PM -0800, Eric Voskuil wrote:&#xA;&gt; A MITM can receive the initial broadcast and then spoof it by jamming the original. You then only see one.&#xA;&gt; &#xA;&gt; e&#xA;&gt; &#xA;&gt; &gt; On Feb 5, 2015, at 2:07 PM, Paul Puey &lt;paul at airbitz.co&gt; wrote:&#xA;&gt; &gt; &#xA;&gt; &gt; So if you picked up the BLE broadcast request. All you know is that *someone* within 100m is requesting bitcoin at a certain address. Not necessarily who. The *name* is both optional, and possibly just a *handle* of the user. If I&#39;m sitting 5 ft away from someone at dinner and wanted to pay them via BLE, I might see &#34;Monkey Dude&#34; on my list and simply ask him &#34;is that you?&#34; If so, I send it. If there are two &#34;Monkey Dude&#39;s&#34; Then I have to bother with the address prefix, but not otherwise.&#xA;&gt; &gt; &#xA;&gt; &gt;&gt; On Thu, Feb 5, 2015 at 1:46 PM, Eric Voskuil &lt;eric at voskuil.org&gt; wrote:&#xA;&gt; &gt;&gt; BLE has an advertised range of over 100m. &#xA;&gt; &gt;&gt; &#xA;&gt; &gt;&gt; http://www.bluetooth.com/Pages/low-energy-tech-info.aspx&#xA;&gt; &gt;&gt; &#xA;&gt; &gt;&gt; In the case of mass surveillance that range could most likely be extended dramatically by the reviewer. I&#39;ve seen  WiFi ranges of over a mile with a strong (not FCC approved) receiver.&#xA;&gt; &gt;&gt; &#xA;&gt; &gt;&gt; WiFi hotspots don&#39;t have strong identity or a guaranteed position, so they can&#39;t be trusted for location.&#xA;&gt; &gt;&gt; &#xA;&gt; &gt;&gt; e&#xA;&gt; &gt;&gt; &#xA;&gt; &gt;&gt; On Feb 5, 2015, at 1:36 PM, Mike Hearn &lt;mike at plan99.net&gt; wrote:&#xA;&gt; &gt;&gt; &#xA;&gt; &gt;&gt;&gt;&gt; This sounds horrible. You could basically monitor anyone with a wallet in a highly populated area and track them super easily by doing facial recognition.&#xA;&gt; &gt;&gt;&gt; &#xA;&gt; &gt;&gt;&gt; We&#39;re talking about BLE, still? The radio tech that runs in the so called &#34;junk bands&#34; because propagation is so poor?&#xA;&gt; &gt;&gt;&gt; &#xA;&gt; &gt;&gt;&gt; My watch loses its connection to my phone if I just put it down and walk around my apartment. I&#39;m all for reasonable paranoia, but Bluetooth isn&#39;t going to be enabling mass surveillance any time soon. It barely goes through air, let alone walls.&#xA;&gt; &gt;&gt;&gt; &#xA;&gt; &gt;&gt;&gt; Anyway, whatever. I&#39;m just bouncing around ideas for faster user interfaces. You could always switch it off or set it to be triggered by the presence of particular wifi hotspots, if you don&#39;t mind an initial bit of setup.&#xA;&gt; &gt;&gt;&gt; &#xA;&gt; &gt;&gt;&gt; Back on topic - the debate is interesting, but I think to get this to the stage of being a BIP we&#39;d need at least another wallet to implement it? Then I guess a BIP would be useful regardless of the design issues. The prefix matching still feels flaky to me but it&#39;s hard to know if you could really swipe payments out of the air in practice, without actually trying it.&#xA;&gt; &gt; &#xA;&#xA;&gt; ------------------------------------------------------------------------------&#xA;&gt; Dive into the World of Parallel Programming. The Go Parallel Website,&#xA;&gt; sponsored by Intel and developed in partnership with Slashdot Media, is your&#xA;&gt; hub for all things parallel software development, from weekly thought&#xA;&gt; leadership blogs to news, videos, case studies, tutorials and more. Take a&#xA;&gt; look and join the conversation now. http://goparallel.sourceforge.net/&#xA;&#xA;&gt; _______________________________________________&#xA;&gt; Bitcoin-development mailing list&#xA;&gt; Bitcoin-development at lists.sourceforge.net&#xA;&gt; https://lists.sourceforge.net/lists/listinfo/bitcoin-development</html></oembed>