-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 2015-06-20 19:19, Eric Lombrozo wrote: >> On Jun 20, 2015, at 4:37 PM, justusranv...@riseup.net wrote: >> >> Signed PGP part >> On 2015-06-20 18:20, Jorge Timón wrote: >> > On Fri, Jun 19, 2015 at 6:42 PM, Eric Lombrozo <elombr...@gmail.com> >> > wrote: >> >> If we want a non-repudiation mechanism in the protocol, we should >> >> explicitly define one rather than relying on “prima facie” >> >> assumptions. Otherwise, I would recommend not relying on the existence >> >> of a signed transaction as proof of intent to pay… >> > >> > Non-repudiation can be built on top of the payment protocol layer. >> >> >> Non-repudiation is an intrinsic property of the ECDSA signatures which >> Bitcoin uses - it's not a feature that needs to be built. >> >> There's no way to accidentally sign a transaction and accidentally >> announce it publicly. There is no form of third-party error that can >> result in a payee receiving an erroneous contract. >> >> > > Justus, > > We don’t even have a concept of identity in the Bitcoin protocol, let > alone non-repudiation. What good is non-repudiation if there’s no way > to even associate a signature with a legal entity? > > Sure, we could use the ECDSA signatures in transactions as part of a > non-repudiation scheme - but the recipient would have to also have a > means to establish the identity of the sender and associate it with > the the transaction. > > > Furthermore, in light of the fact that there *are* fully legitimate > use cases for sending conflicting transactions…and the fact that > determination of intent isn’t always entirely clear…we should refrain > from attaching any further significance transaction signatures other > than that “the sender was willing to have it included in the > blockchain if a miner were to have seen it and accepted it…but perhaps > the sender would have changed their mind before it actually did get > accepted.”
Bitcoin has no concept of identity, but in any type of commercial transaction the parties involved must know some minimal amount of identity information in order to transact at all. Except for some identifiable special cases, I think a payee is perfectly justified in treating a double spend of a payment sent to them as part of a commercial transaction as a fraud attempt and employing whatever non-Bitcoin recourse mechanisms, if any, they have access to. - From the perspective of the network, the obviously correct action for any node or miner is to relay the first version of any transaction they see. The primary purpose of mining is to resolve this otherwise-unresolvable problem of determining which transaction among a set of conflicting transactions happened first. If a node or miner wants to deviate from the obviously correct behaviour, and if they want to avoid harming the value of the network, they should be particularly careful to make sure their deviation from "first seen" doesn't introduce harmful unintended side effects, like making fraud easier. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJVhgTgAAoJECpf2nDq2eYjkksQAJyRVhT2vNQUqlOfH9Z/9EeT LkUm8eg3f1i3xhJVxtLGVJkRmMYmuNtH0lIsH/B3iED732oZSzhwM1F5ky948Mw7 FFG65iUTrXVup9eKZuD7T3/FaQHfC5YME36F4UvEtSUcRDUKmongRGuuw7sNv617 APl3MDwZ8tVWaDb7yZ251is6Fx1l3b6tR4tHUzyIWPyIOuXOsyUaoS1cYJ00YcI5 WIzIXIlRDNpvpIXv4NFtr0BH6BmTCCZOJH3X9Hmtxqrg/dlnfnmc1pZgAyqRXj1d 5of7dYwb+bhHpU9TvcDYprN55Kmida2gTZewfr33rTXcVyjhs5N3bmIRIRrPltMA fFqlKJ7Fo4ldyJ4OEK6upuFHwmQRNL7qr/ODmYg83rJj3BdTzXsJ1l3BRAUBS+cm gc8Q3urxmVyspht+U64GO+ieLA9xb9izFMa+GL8nag0VuHc5J7XDjfzXBT8VK5be 646AZ0tFULNLOBWEJuBRbCRUs90YK2ePpGnAwiZ7HuwHMAC333FYiBuRxgwgn+xv hHMlQWTtrl0zJrxD+pcb5axC7zQdVHVeyNJDi4RF1Wau2NX/itHcUqRr75N8/Si+ GPF8JSnvLlplEsEMBAtbKvg4dn1AOEuJpXtDYrWrzZDs+/wwz5PfQ2oCZ3YRHNx2 po6di9uOSlLq0BJJfSrM =HbNG -----END PGP SIGNATURE----- ------------------------------------------------------------------------------ _______________________________________________ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
