RE: Associating symmetric algorithms with a public key

"Trevor Freeman (Exchange)" <trevorf@Exchange.Microsoft.com> Tue, 16 November 1999 21:24 UTC

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From: "Trevor Freeman (Exchange)" <trevorf@Exchange.Microsoft.com>
To: 'Paul Koning' <pkoning@xedia.com>
Cc: ietf-pkix@imc.org
Subject: RE: Associating symmetric algorithms with a public key
Date: Tue, 16 Nov 1999 10:56:34 -0800
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This is a hint as to what to use, nothing more. 
If I have you public key and want to encrypt a file, I could guess what
symmetric algorithms to use. It does not hold that if I have publicise the
set of symmetric algorithms on my workstations, every public encryption key
I have in a certificate would successfully decrypt data with any of the
symmetric algorithms.  The key exchange world complete successfully, and you
client would know the session key, but it is not guaranteed that that code
with the session key would have access to every symmetric algorithms
implementation on you workstation.

-----Original Message-----
From: Paul Koning [mailto:pkoning@xedia.com]
Sent: Tuesday, November 16, 1999 10:20 AM
To: Trevor Freeman (Exchange)
Cc: ietf-pkix@imc.org
Subject: Re: Associating symmetric algorithms with a public key


>>>>> "Exchange" == Exchange  <Trevor> writes:

 Exchange> There are a number of applications which need a hint as to
 Exchange> the set of symmetric algorithms which can be used with a
 Exchange> public key from a certificate for encrypting data with
 Exchange> asynchronous applications. 

I'm puzzled by this.  What connection is there between a public key
and a set of supported, or permitted, symmetric algorithms?  I just
don't see the relationship.

	paul