Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site petrus.UUCP Path: utzoo!watmath!clyde!burl!ulysses!gamma!epsilon!zeta!sabre!petrus!karn From: karn@petrus.UUCP (Phil R. Karn) Newsgroups: net.ham-radio Subject: Re: Ham Radio and Computer Networking Message-ID: <477@petrus.UUCP> Date: Thu, 22-Aug-85 13:48:14 EDT Article-I.D.: petrus.477 Posted: Thu Aug 22 13:48:14 1985 Date-Received: Sat, 24-Aug-85 16:33:29 EDT References: <312@harvard.ARPA> <168@bunny.UUCP> Distribution: net Organization: Bell Communications Research, Inc Lines: 26 > "The transmission by radio of messages in codes or ciphers in domestic > and international communications to or between amateur stations is > prohibited. All communications regardless of type of emissions employed > shall be in plain language except that generally recongnized > abreviations established by regulation or custom and usage are > permissible as are any other abreviations or signals where the intent is > not to obscure the meaning but only to facilitate communications." There has been considerable discussion on the topic of authentication vs encryption in the amateur service. So far, the consensus is that the FCC doesn't prohibit the use of codes as long as they are for the purpose of authenticating the sender and not for the purposes of hiding what he's saying. A precedent: touch tone codes for repeater control and so forth. (There is a special exception that allows encryption on amateur satellite control links, but that doesn't apply here.) Paul Newland, AD7I, presented a paper suggesting several possible schemes in this year's ARRL Computer Networking Conference. The basic idea is to calculate some function over a packet, encrypt it and send it along with the packet (which would be in plain text). Any modification or forgery of the packet would likely cause the encrypted check number not to match. You might think of this as a "checksum" or "CRC" function whose intent is to protect against intentional corruption by an intelligent human instead of random corruption by natural processes like noise. Phil