Newsgroups: sci.crypt
From: (Terry Ritter)

Subject: Re: Ladder DES
Message-ID: <>
Organization: Capital Area Central Texas UNIX Society, Austin, Tx
References: <> <2kejt8$
+           edu>
Date: Fri, 25 Feb 1994 17:52:56 GMT

 In <2kejt8$>
 (Anonymous) writes:

>Another, already somewhat widely used alternative is
>RSA Data Security's "DESX", as implemented in their commercial
>products MailSafe and BSAFE since 1986/87.  DESX is ordinary
>DES with pre- and post-processing to expand keysize and
>security.  Like Ladder DES, it is faster than triple-DES.

 I don't find it in the RSA FAQ.  Where was this design published
 openly for comment?  What were the comments?

>I have some reason to believe that RSA may be willing to
>allow use of DESX free of licensing fees.  Perhaps someone
>from RSA would comment?

 What is the patent number?  Without a patent, there is no need to
 ask permission.