The discussion of computer security threats addresses the essentials of computer security and presents case histories of computer crime. Security management considerations cover organizational features of electronic data processing security, information protection, and personnel screening and management. Issues in computer physical security include access control, environmental security, and disaster control. Communications security issues encompass line security, transmission security, cryptographic security, emission security, and technical security. Systems security topics are systems identification, isolation in computer systems, systems access control, detection and surveillance, systems integrity, recordkeeping, and systems reliability. The discussion of threat evaluation considers the cost of countermeasures and loss, types of loss, computer programmed threat evaluation, and the security survey. Appended sample log forms, glossary, 128-item bibliography, and subject index.