[6745] in cryptography@c2.net mail archive
Re: time dependant
daemon@ATHENA.MIT.EDU (Michael Paul Johnson)
Tue Mar 7 23:36:58 2000
Message-Id: <4.3.2.20000307162109.00b78b70@ebible.org>
Date: Tue, 07 Mar 2000 16:22:49 -0700
To: "Arrianto Mukti Wibowo" <iscp9063@nus.edu.sg>,
"Cryptography" <cryptography@c2.net>
From: Michael Paul Johnson <mpj@ebible.org>
In-Reply-To: <010601bf8879$2f4c1980$82d08489@muki>
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At 05:05 3/8/2000 +0800, Arrianto Mukti Wibowo wrote:
>Hi,
>
>I want to know whether there is a crypto building block which doesn't allow
>someone to open an encrypted message before a certain date.
>
>[Damn hard. Math functions don't grok "date". The only reasonable way
>to do this without a trusted third party is to pick an encryption
>algorithm that will take at least as long to decrypt (in likely
>available computer time) as are needed. -Perry]
Perry is right. If you have a trusted third party with a secure location,
you could simply have the trusted third party release the key on the
appointed date.
_______
Michael Paul Johnson
http://ebible.org/mpj
