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Date: Thu, 23 Jul 2015 11:48:08 +0200
From: Thomas Voegtlin <thomasv@electrum.org>
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Subject: Re: [bitcoin-dev] Proposal: extend bip70 with OpenAlias
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Le 17/07/2015 03:01, Justin Newton via bitcoin-dev a =E9crit :
>> 3> We use a 2 tier lookup format. [...]
>>
>> We do the same thing, except in a single call. [...]
>=20
> We looked at doing this in a single lookup as you did.  With one or two
> currencies this can be potentially more efficient.  As the number of
> supported currencies and addresses under a single name grows, however, =
this
> solution becomes potentially more problematic. [...]

Hi Justin,

Your lookup solution is indeed more efficient than OpenAlias, and more
robust to DoS. However, that is not because you use a two-tier lookup.

Indeed, instead of having the following records:
_wallet.sample =3D "btc ltc"
_btc._wallet.sample =3D "mybitcoinadress"

you could simply have:
_wallet.sample =3D "btc ltc"
_btc.sample =3D "mybitcoinaddress"

In practice, a wallet supporting only Bitcoin will skip the currencies
lookup in both cases, and go directly for the _btc record.

One benefit of having an intermediate "_wallet" level is to allow zone
delegation. Is that the reason for that choice?

Thomas