Re: 2047 bit keys in PGP

At 05:17 AM 1/4/96 +0000, you wrote:

>
>> Why is there a limit to the size of the key anyway? It's too bad PGP 
>> doesn't support any size key (within reason).
>
>Within reason is the Key Phrase.  Even with a Pentium 90, I notice a 
>considerable lag in decrypting messages that have been encrypted with 
>a key larger than 2047/8.
>
>Even if you have a fast machine, if the person recieving the message 
>could wait a long time to decrypt you 4096 byte encrypted message.

It seems to me that the best argument AGAINST supporting (and using) keys
greater than 2048 bits is the false sense of security created.  Even
1024-bit keys will probably be safe for decades if just the algorithm is
concerned.  Far more threatening are various other attacks, including RF
snooping in combination with specialized viruses, as well as black-bag jobs
on hardware.

Why build a castle with a front wall a mile high when the back wall is a
5-foot chain-link fence?!?

Hello,

On Wed, 3 Jan 1996, jim bell wrote:

> It seems to me that the best argument AGAINST supporting (and using) keys
> greater than 2048 bits is the false sense of security created.  Even
> 1024-bit keys will probably be safe for decades if just the algorithm is
> concerned.  Far more threatening are various other attacks, including RF
> snooping in combination with specialized viruses, as well as black-bag jobs
> on hardware.

  I have been reading this discussion, and I would recommend that someone 
show the time that Bruce Schneier has in his book "Applied Cryptography" 
(2nd ED), as he covers the security of different key lengths very well.  
I would also suggest that people read it if this is a topic that 
interests them, as it was written very well. 
  I would quote from it, except that I am at work, and the book is in my 
dorm room. :)
  Enjoy and have fun.

==========================================================================
James Black (Comp Sci/Comp Eng sophomore)
e-mail: black@eng.usf.edu
http://www.eng.usf.edu/~black/index.html
"An idea that is not dangerous is unworthy of being called an idea at all."
Oscar Wilde 
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