Re: decryption of string

From: Mike (sorry@sorry.com)
Date: 02/05/03 

From: "Mike" <sorry@sorry.com>
Date: Wed, 5 Feb 2003 08:22:29 -0600

"TC" <a@b.c.d> wrote in message news:1044420835.390108@teuthos...
> I asked the group some time ago whether it was a common property of
> asymmetric ciphers, that you could encrypt with *either* key:
> 3964f176.0211201623.335ba298@posting.google.com
>
> The concensus in reply - as I understood it - was "no". Ie. most (all?)
> asymmetric ciphers require you to encrypt with the public key & decrypt
with
> the private one. But above, they seem to be encrypting with the *private*
> key & decrypting with the public one.
>
> Am I missing something (as usual)?

I'm thinking it's similar to digital signature verification. In that case,
you use MD5 against the original message and then use your private key to
encrypt it.

The recipient uses the sender's public key to decrypt that and compares it
to their own MD5 hash of that very message.

When you use the MD5 hash, you are essentially making it a one-way
encryption. However, you don't have to use the hash function, but I'm sure
this has a number of security hazards that must be evaluated. 

--
Mike

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