Re: [Bitcoin-development] alternate proposal opt-in miner takes double-spend (Re: replace-by-fee v0.10.0rc4)

[Justus Ranvier <justusranvier@riseup.net>]

[-- Attachment #1: Type: text/plain, Size: 2013 bytes --]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 02/22/2015 07:50 AM, Matt Whitlock wrote:
> This happened to one of the merchants at the Bitcoin 2013
> conference in San Jose. They sold some T-shirts and accepted
> zero-confirmation transactions. The transactions depended on other
> unconfirmed transactions, which never confirmed, so this merchant
> never got their money.
> 
> I keep telling people not to accept transactions with zero
> confirmations, but no one listens.

A better solution is to track the failure rate of zero confirmation
transactions, and adjust prices accordingly to cover the expected loss.

This is what every merchant *already does* since no payment method has
a 0% fraud rate.

Even physical cash has a probability of being counterfeit, and the
prices you pay for things at a convenience store already have that
risk priced in.

The idea that zero confirmation transactions require a 100% guarantee
is a strawman, especially since there exists no number of
confirmations the actually produce a 100% irreversibility guarantee.

Zero confirmation transactions can work as long as the risk of
reversal is measurable and reasonably stable.
-----BEGIN PGP SIGNATURE-----
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=fVAx
-----END PGP SIGNATURE-----

[-- Attachment #2: 0xEAD9E623.asc --]
[-- Type: application/pgp-keys, Size: 17801 bytes --]