Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!netsys!vector!telecom-gateway From: portal!cup.portal.com!David_Michael_McCord@apple.com Newsgroups: comp.dcom.telecom Subject: Re: Myth and Reality About Eavesdropping Message-ID: Date: 20 Jul 89 04:13:34 GMT Sender: news@vector.Dallas.TX.US Lines: 21 Approved: telecom-request@vector.dallas.tx.us X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@vector.dallas.tx.us X-TELECOM-Digest: volume 9, issue 247, message 10 of 10 Mr. Lippman's detailed article regarding detection of wiretaps was quite interesting reading. However, there is yet another possible method to implement a "wiretap" (reason for quotes will become apparent) that is totally impossible to detect, because it does not even cause the very-slight changes Mr. Lippman discussed. On any line served by an all-digital switch, all line signals pass through a digital cross-connect device which is essentially a large block of random access memory (RAM). Connections through this device are made by simply copying the digital image of the line audio signals from one RAM location (address) to another. It does not require a degree in computer science to see that the digitized audio may be copied just as easily to a second location, thus allowing completely undetectable monitoring of the line in question. I do not *know* that software to perform this function exists. But I suspect that it would only take fifteen minutes for a #5ESS-trained programmer to write it... A wiretap without any wire! David@cup.portal.com