[Bitcoin-development] Key retirement and key compromise

[Roy Badami]

On Mon, Mar 25, 2013 at 02:10:53PM -0700, Gregory Maxwell wrote:
> On Mon, Mar 25, 2013 at 1:49 PM, Roy Badami <roy at gnomon.org.uk> wrote:
> > I'm not envisaging something as drastic as changing the rules to make
> > transactions to revoked addresses invalid - just an overlay protocol.
> > Although to be useful such a protocol would have to be pretty much
> > universally implemented by clients.
> 
> That is quite drastic enough, as it requires adding more perpetual
> data that must remain in fast lookup for all validating nodes (the set
> of revoked 'addresses').

Maybe it should be possible for addresses to contain expiry dates, so
that revocation lists don't need to hang around forever.

> Keep in mind that this is only improvement for what is a usually
> inadvisable usage of Bitcoin to begin with... you should not be
> reusing addresses.

It may be inadvisable but in many cases it is pretty much unavoidable
as Bitcoin stands today.  Granted, the payment protocol will help with
that in many use cases...

roy