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Cc: bitcoin-development@lists.sourceforge.net
Subject: Re: [Bitcoin-development] Proposal for a new opcode
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Sounds interesting, however, even after a couple of days, I cannot see =
how you maintain protection against double spend using OP_CHECKEXPSIG. =
It is not until you redeem the OP_CHECKEXPSIG transaction that you =
reveal which former transactions that was involved?
I guess I am missing a point here?
/M
=20
On 02/03/2012, at 20:57, Watson Ladd wrote:
> Dear all,
> I am proposing a new opcode for the purposes of anonymous
> transactions. This new opcode enables scripts to be given proof that
> the receiver can carry out or has carried out a previous transaction.
> I'm currently working on a paper that discusses using this opcode for
> anonymous transactions.
>=20
> Name: OP_CHECKEXPSIG
> Stack before: <sig><pk><hash>
> Stack after: T/F, where is true if sig is a ECDSA signature under pk
> for the hash hash. (Hash is the hash of a message).
> Uses: Preexisting digital cash techniques relied on keeping track of a
> list of turned in notes to forbid double spending. Using
> OP_CHECKEXPSIG we can instead pass the script that gives the nth note
> value proof that the notes {1,...n-1} were turned in and are distinct.
> This enables a coupling of the strong double spend protection of
> Bitcoin with traditional digital cash's strong anonymity.
>=20
> Sincerely,
> Watson Ladd
>=20
> =
--------------------------------------------------------------------------=
----
> Virtualization & Cloud Management Using Capacity Planning
> Cloud computing makes use of virtualization - but cloud computing=20
> also focuses on allowing computing to be delivered as a service.
> http://www.accelacomm.com/jaw/sfnl/114/51521223/
> _______________________________________________
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