Re: 128bit RSA public key - time to break?

From: Paul Crowley (paul@JUNKCATCHER.ciphergoth.org)
Date: 02/23/03 

From: Paul Crowley <paul@JUNKCATCHER.ciphergoth.org>
Date: Sun, 23 Feb 2003 17:25:08 GMT

"Shane Hird" <shanehird@hotmail.com> writes:

> Yep.. The key will be used as an identifier as well, which has already
> been fixed to 128 bits. For backwards compatibility it would be good
> to use those same bits for the public key.

In that case you have no problem. Use whatever PK system you like,
and use SHA-1 to hash the public key, truncating the output to 128
bits; this is sometimes called a key "fingerprint". Transmit the full
public key along with everything you sign, and you'll be able to
verify that it came from that ID. 

-- 
  __  Paul Crowley
\/ o\ sig@paul.ciphergoth.org
/\__/ http://www.ciphergoth.org/

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