rich1.0npub1ac86vemj7ce5z8jyxt39rna3tvwql6xd30ha3vxcd6esysp23d9qrlswfjhttps://nostr.ae/npub1ac86vemj7ce5z8jyxt39rna3tvwql6xd30ha3vxcd6esysp23d9qrlswfjnjumphttps://nostr.ae📅 Original date posted:2014-03-21 📝 Original message:Maybe its time to explore raw ECDSA signed message based certs. btw I dont think its quite 4kB. eg bitpay's looks to be about 1.5kB in der format. And they contain a 2048-bit RSA server key, and 2048-bit RSA signatures (256byte each right there = 512bytes). And even 2048 is weaker than 256-bit ECDSA. Adam On Fri, Mar 21, 2014 at 11:25:59AM +0100, Andreas Schildbach wrote: >On 03/20/2014 01:12 PM, Adam Back wrote: > >> Whats a sensible limit on practical/convenient QR code size? > >Technically 3 KB. In my experience codes above 1.5 KB become impossible >to scan (ZXing scanner, 3 years ago). You will want to stay below 500 >bytes for convenient scanning. That said, I'm convinced there is a lot >of room for scanning improvements. > >> How much of the payment protocol message size comes from use of x509? > >As said in the OP, a minimal PR uses 50 bytes. X.509 seems to put about >4000 bytes on top of that. > >As you can see, we have quite some room for improvements to PR payload >(PaymentDetails). X.509 certification will probably not be possible via >QR, at least not until specialized CA's will issue space-efficient certs >(using ECDSA?).