[bitcoin-dev] Address expiration times should be added to BIP-173

Andreas Schildbach andreas at schildbach.de
Thu Sep 28 15:06:56 UTC 2017


On 09/28/2017 04:41 PM, Sjors Provoost via bitcoin-dev wrote:

>> The payment request message is just as one-way as an address is. It is
>> already being emailed and printed on an invoice, in fact it often acts
>> as the invoice.
> 
> True and the more complicated fields, like a digital signature, are optional. Are you suggesting BIP-70 payment requests should be rendered with bech32? How long would those be if it's just the address and expiration date?

I've not yet progressed that far in segwit support, but I can't think of
a reason why not. You can request coins to any script using the payment
protocol.

Regarding size, I've had no problems putting (unsigned) payment request
messages into QR codes. I doubt paying to a native segwit address will
change much in size. Protobuf is very efficient.


>> Even more problematic, if you were to include an expiry date in a
>> BIP-173 address and put that into a payment request, wallets wouldn't be
>> allowed to parse that expiry date from the script without violating the
>> BIP70 spec.
> 
> Do tools that generate BIP-70 payment requests generate addresses themselves or are those input manually by a user? In the former case, I assume it could avoid setting the optional expiration date?

The BIP70 spec doesn't limit you on this, I guess either does exist.
Having two (or more!) optional expiration date adds unnecessary
complexity to the specs and implementations. E.g. what if the two do not
match up?

> Is it not allowed to scan the date even if it then sets the expires field to the same (redundant) value?

What do you mean by "scan the date"?



More information about the bitcoin-dev mailing list