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SCIENCE OF ELECTRONIC SURVEILLANCE

NCJ Number
45215
Author(s)
J S VANDERWERKER; R B ASHBY
Date Published
1976
Length
181 pages
Annotation
PRINCIPAL FINDINGS OF THE NATIONAL WIRETAP STUDY AND SUBSEQUENT ANALYSIS ARE PRESENTED; EQUIPMENT CAPABILITY IS GIVEN FOR AUDIO EAVESDROPPING, RADIO EAVESDROPPING, COUNTERMEASURES, NONAUDIO INFORMATION, VISUAL SYSTEMS.
Abstract
THE NUMEROUS DEVICES AVAILABLE FOR TELEPHONE EAVESDROPPING, RADIO TRANSMISSION, PASSIVE AND ACTIVE LISTENING AND RECORDING, AND INTERCEPTION OF NONAUDIO INFORMATION (TELETYPES, TELEPRINTERS, AND PHOTOCOPYING MACHINES) ARE DESCRIBED IN DETAIL. AUDIO SYSTEM ACCESSORIES AND SOPHISTICATED EAVESDROPPING TECHNIQUES USING LASERS, MICROWAVES, AND NONLINEAR REFLECTORS ARE EXAMINED. A SEPARATE SECTION GIVES A STATE-OF-THE-ART REVIEW OF COUNTERMEASURES EQUIPMENT. ALTHOUGH IT IS EXTREMELY DIFFICULT TO DETECT A PROPERLY INSTALLED TELEPHONE INTERCEPTION DEVICE, MANY DEVICES ARE ON THE MARKET WHICH CAN ALERT THE USER TO THE POSSIBILITY OF A TAP. TO THIS END, SUCH COUNTERMEASURES AS COUNTERSURVEILLANCE RADIO RECEIVERS, TELEPHONE ANALYSIS EQUIPMENT, ELECTRONIC AIDS TO PHYSICAL INSPECTION, AND PROTECTION DEVICES (E.G., ACOUSTIC ROOMS, DISCONNECT DEVICES, FILTERS, AND VARIOUS RADIO AND MAGNETIC JAMMERS) ARE DISCUSSED. COMPUTER SECURITY IS DISCUSSED, AS THIS IS BY FAR THE MOST ACTIVE AREA IN NONAUDIO EAVESDROPPING. TECHNICAL SKILLS REQUIRED ARE MODERATE BUT THE REWARDS ARE EXTREMELY ATTRACTIVE FOR THE SKILLED, PROFESSIONAL CRIMINAL. INTERCEPTION AND MANIPULATION OF DATA OCCURS BETWEEN A TIME-SHARED COMPUTER SUBSCRIBER'S REMOTE TERMINAL AND THE CENTRAL COMPUTER. SIGNAL RECEPTION CAN BE IMPLEMENTED THROUGH USE OF STANDARD AUDIO EAVESDROPPING DEVICES AND IS DIFFICULT TO TRACE. EAVESDROPPING ON SUCH INFORMATION PROCESSING MACHINES AS TELEPRINTERS, COMPUTER TERMINALS, AND ELECTRIC TYPEWRITERS IS DIFFICULT AND NOT PARTICULARLY REWARDING. IT WAS ALSO FOUND THAT EXTENSIVE ELECTRONIC ASSISTANCE IS AVAILABLE TO LAW ENFORCEMENT AND SECURITY ORGANIZATIONS FOR NIGHT VIEWING AND VEHICLE OR CARGO TRACKING. THE MARKET FOR THESE AIDS IS GREATER THAN FOR AUDIO EAVESDROPPING DEVICES; ALL ARE APPARENTLY LEGAL. SEVERAL NEWER TECHNOLOGIES WERE IDENTIFIED WHICH ALLOW SIMULTANEOUS TRACKING OF MANY VEHICLES FROM A SINGLE CONTROL STATION. THESE SYSTEMS, WHILE USEFUL TO LAW ENFORCEMENT, ARE PRIMARILY INTENDED FOR CIVIL USE IN TRAFFIC AND MASS TRANSIT SYSTEMS MANAGEMENT. FUTURE DEVICES ARE EXPECTED TO BE SMALLER AND HAVE BETTER PERFORMANCE CHARACTERISTICS. IT IS CONCLUDED THAT IT WOULD BE VERY DIFFICULT TO CONTROL WIRETAPPING BY CONTROLLING THE EQUIPMENT BECAUSE STANDARD ELECTRONIC PARTS CAN EASILY BE ASSEMBLED INTO A LISTENING DEVICE. IT IS ALSO CONCLUDED THAT CLAIMS MADE FOR COUNTERMEASURES ARE FREQUENTLY MISLEADING AND THAT SUCH MEASURES SHOULD NOT BE RELIED UPON EXCLUSIVELY FOR SECURITY. (GLR)