Date: Sun, 18 Dec 1994 21:15:19 EST From: "Rob Slade, Social Convener to the Net" Subject: "For the Sake of Elena" by George BKSELENA.RVW 941101 "For the Sake of Elena", George, 1992, 0-553-56127-8, U$5.95/C$6.95 %A Elizabeth George %C 1540 Broadway, New York, NY 10036 %D 1992 %G 0-553-56127-8 %I Bantam Books %O U$5.95/C$6.95 %P 442 %T "For the Sake of Elena" Elizabeth George writes very good mystery novels. I hesitate to use the phrase, "in the great British mystery tradition," since she has extended the genre by a population of very real characters and studies, in depth, of human motivations. So where is the technology and/or science fiction? The plot in this particular book partly hangs on a call made via "Ceephone". This is the British version of the American TDD (Telecommunications Device for the Deaf). Part of the story looks at whether the call was made at all, part hangs on whether such a call could be spoofed. In North America, local calls, unless made through a PBX (Private Branch eXchange, a privately operated telephone switch) or recorded on Automatic Number Identification (ANI, also known as "Caller-ID") would not be recorded. England, however, has local measured service. I would therefore have thought that identifying whether a call was made would be a simple task. It is possible, though, that the only record is that you made a call for a certain time within a certain zone. A Ceephone is basically a terminal/modem combination. The American TDD, I believe, uses a standard 300 bps B.11 103 modem. 300 bps is ample speed because a TDD is essentially a "talk" or "CHAT" function: what I type appears on your screen, and what you type appears on mine. At first glance, therefore, the uninitiated would say that such a system is easy to spoof. There is no voice to recognize, so it would be easy to fool someone. This, however, is an overly simplistic view. As anyone who uses talk, CHAT or PHONE knows, everyone is an individual. How do they start the conversation? Do they use capital letters or not? Do they use abbreviations? What type? And, speaking of typing, how fast can they? How well can they? How many mistakes do they make? How far back are they willing to erase to correct a mistake? For anyone who has used such a system for any time, it is almost impossible to change between two people even if the party on the remote terminal doesn't know them. Faking someone else is pretty much out of the question. Not even people can pass the Turing test. copyright Robert M. Slade, 1994 BKSELENA.RVW 941101 ====================== DECUS Canada Communications, Desktop, Education and Security group newsletters Editor and/or reviewer ROBERTS@decus.ca, RSlade@sfu.ca, Rob Slade at 1:153/733 Author "Robert Slade's Guide to Computer Viruses" 0-387-94311-0/3-540-94311-0