Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site wdl1.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!cornell!uw-beaver!tektronix!hplabs!hpda!fortune!wdl1!jbn From: jbn@wdl1.UUCP Newsgroups: net.micro.pc Subject: Re: Re: software protection - dongles Message-ID: <654@wdl1.UUCP> Date: Thu, 22-Aug-85 20:25:20 EDT Article-I.D.: wdl1.654 Posted: Thu Aug 22 20:25:20 1985 Date-Received: Sun, 25-Aug-85 13:15:07 EDT Sender: notes@wdl1.UUCP Organization: Ford Aerospace, Western Development Laboratories Lines: 11 Nf-ID: #R:entropy:-17600:wdl1:5000017:000:545 Nf-From: wdl1!jbn Aug 14 16:25:00 1985 No, you can't break a good dongle by looking at its inputs and outputs, although you may be able to do so by analyzing the software that polls it. Good dongles work like Identify-Friend-Foe devices; the program challenges the dongle by sending it a random number, which it runs through an encryption algorithm, returning the result, which is then checked by the program. The challenge is never the same twice. Three iterations through the DES algorithm with different keys for each iteration is probably pretty solid. John Nagle