encrypt with GPG 1.0.4 decrypt with ViaCrypt 4.0 problem

[Len Sassaman]

On Thu, 4 Oct 2001, Alex Frenklakh wrote:

> Len,
>
> thanks for your suggestions,
>
> It looks like Viacrypt 4.0 might be using a hybrid cipher of
> RSA/IDEA and we'd have to modify our gnupg with the idea.c
> fix, which violates the US patent, as I understand.
> Not sure whether it's the V3 RSA key problem .. have to look into
> that.

OpenPGP uses a combination of public key and symmetric key encryption. In
early versions (PGP 2.x, Viacrypt 4.0), IDEA and RSA are the two ciphers
used. (Not a hybrid, but actually both ciphers.)

If you want to work with Viacrypt, you need V3 keys, which require RSA and
IDEA.