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Re: A problem with public key encrption in IKE

     I thought one reason for having both signatures and public key 
     encryption as authentication methods is that signatures provide 
     non-repudiability while public key encryption provides repudiability.  
     In some cases you may want one, and in some cases the other.
     
     Also, public key provides stronger security because an attacker would 
     have to break both DH and RSA to obtain the key material derived from 
     the exchange.  With signatures the attacker only needs to break DH. 
     (Granted, this may be good enough.)
     
     It would be nice to be able to enjoy the benefits of the public key 
     encryption method even in cases where the initiator does not know the 
     public key of the responder at the beginning of the exchange.
     
     Francisco
     


______________________________ Reply Separator _________________________________
Subject: Re: A problem with public key encrption in IKE
Author:  Non-HP-kivinen (kivinen@ssh.fi) at HP-ColSprings,mimegw5
Date:    12/13/99 6:59 AM


francisco_corella@hp.com writes:
> It should be possible to fix these two problems, probably at the expense of 
> additional messages, by first establishing the DH secret, then exchanging 
     
Use signatures based authentication method, instead of rsa encryption. 
There IS a reason why we have different types of authentications in 
the IKE. They offer little bit different things...
-- 
kivinen@iki.fi                               Work : +358-9-4354 3218 
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