INTEGRATION OF TIME DIVISION SPEECH SCRAMBLING INTO POLICE TELECOMMUNICATION NETWORKS (FROM INTERNATIONAL CONFERENCE ON CRIME COUNTERMEASURES - SCIENCE AND ENGINEERING, 1977, BY JOHN S JACKSON - SEE NCJ-56184)

• NCJ Number: 56195
• Author(s): W BASCHLIN
• Date Published: 1977
• Length: 4 pages
• Corporate Author: Ores Publications
• Publication Format: Document
• Language: English
• Country: United States of America

Annotation

THIS ARTICLE DISCUSSES THE OPERATION OF EXISTING TIME DIVISION SPEECH SCRAMBLERS, AND STUDIES THEIR INTEGRATION INTO POLICE COMMUNICATIONS NETWORKS FOR PROTECTION FROM EAVESDROPPING.

Abstract

AS PART OF THE 1977 INTERNATIONAL CONFERENCE ON CRIME COUNTERMEASURES, THIS CONTRIBUTION FROM THE SWISS CORPORATION OF BROWN, BOVERI AND COMPANY, DESCRIBES THE OPERATION OF ITS PRODUCTS IN THE PROTECTION OF POLICE COMMUNICATION. EAVESDROPPING IS CONSIDERED A SERIOUS PROBLEM FOR POLICE COMMUNICATION, ESPECIALLY WHEN POLICE RELY ON EXISTING TELEPHONE NETWORKS. EVEN IF THE FIRST PRIORITY IS THE PROTECTION OF POLICE RADIO CHANNELS FROM EAVESDROPPING, THE PROTECTION SYSTEMS SHOULD ALLOW EXPANSION INTO THE TELEPHONE NETWORK. SUCH INTEGRATED SYSTEMS FOR BOTH RADIO AND TELEPHONE HAVE BEEN DEVELOPED BY BROWN BOVERI, AND FEATURE TIME DIVISION SCRAMBLING. THE CRYPTOPHON 1100 AND THE PORTABLE VERICRYPT 1100 SYSTEMS ARE DESCRIBED AS MODERN EXAMPLES OF TIME DIVISION SPEECH SCRAMBLERS WHICH MAY BE INTEGRATED INTO TYPICAL POLICE NETWORKS. THE TIME DIVISION SCRAMBLING PROCESS INTRODUCES A DELAY OF 0.5 SECONDS IN THE TRANSMISSION OF A RADIO SIGNAL. THE SEGMENTS OF SPEECH THAT MAKE UP THE MESSAGE ARE TRANSPOSED BEFORE TRANSMISSION, AND THEN RECONSTRUCTED BY THE RECEIVER. ADDITIONAL TECHNICAL INFORMATION IS PROVIDED. GRAPHIC DATA IS PRESENTED. (TWK).