Dennis Longley

Information Security for Managers

Part 1: security policy and organizational structure personnel and responsibilities access control and cryptographic controls information flow control security of stored data monitoring and audit trails military and commercial security. Part 2: risk analysis and management conventional computer security risk analysis and management Courtney Technique of risk analysis Cramm risk analysis. Part 3: physical security access control personal computer security contingency planning insurance. Part 4: network security security on IBM systems OSI security. Part 5: identify and authentication of the user PINS privacy, integrity and authentication of financial messages financial network security. Part 6: communications and logical security physical security of office systems procedural and personnel security. Part 7: data protection legal protection of information assets computer crime law and personnel.

Data & Computer Security

data type. In data structures, a data type that is defined solely in terms of the operations that can be performed on objects of that type and the range of values that it can take, without regard to the method of representation of the value. See

IBM PC Graphics

The boards described in this section cover the following areas: i Monochrome graphics ii Colour graphics iii Videodisk/tape controllers iv Digitisation v Multifunction graphics.

Files and Records

One of the problems facing the new computer user is that everyday, rather vague terms have very specific meanings when used in the context of computer applications. In this chapter the terms file, record and field are defined and described; these terms relate to the storage of information between computer runs and to the manner that this storage is organised.

How to Build an IBM XT Lookalike

With the IBM PC expansion boards now available it is possible to configure a system that uses the minimum of IBM components. For example, if a PC, not the XT hard disk version, is obtained with only one floppy disk drive, 64 Kb of memory and the keyboard (even that does not have to be IBM) this configuration can be expanded to become a 64 Kb system with a hard disk, colour/graphics monitor, serial/parallel ports, clock/calendar and be fully compatible with the XT.

IBM PC Networking

When two or more microcomputers are linked together they form a network. There are many reasons why it is desirable to join up microcomputers, the more important include: i sharing of common files ii sharing of expensive peripherals such as printers and, disks iii passing messages and completing transactions between users on the network.

APPLE II Networking

When two or more microcomputers are linked together they form a network. There are many reasons why it is desirable to join up microcomputers, the more important include: i sharing of common files ii sharing of expensive peripherals such as hard disks and printers iii passing messages and completing transactions between users on the network.

Compilers, Interpreters and Assemblers

When a computer performs a task it obeys a set of machine code instructions that are fed in sequence to the central processing unit. Each instruction represents a minuscule operation of the computer hardware. When a programmer describes the tasks to be performed by the machine he finds it more convenient to express the actions in terms of the desired results rather than the detailed machine operations (see Chapter 7). Thus the programmer states what overall operations are required whilst the computer demands extremely detailed step-by-step instructions. Fortunately computer programs have been written that accepts the programmer’s statements as input and produces the corresponding detailed machine code as output. These programs are known as translators and they come in three varieties: compilers, interpreters and assemblers.

An Integrated Spreadsheet Package

Traditionally the computer user was faced with the choice of writing a detailed program in a high level language or employing a software package designed for a well specified task. Given a substantial task, common to a large population of users, e.g. sales ledger, word processing, it was clearly profitable to seek out and purchase a proprietory package designed for one’s particular application area and hardware configuration. Nevertheless there remained a host of potential applications which did not justify the cost and effort of seeking, evaluating and purchasing a software package. The alternative of programming, in a high level language, however, all too often proved to be too time consuming to justify computerisation of the task. This situation was particularly true for computer users without extensive programming experience who necessarily expended additional effort in consulting manuals, experimenting with programming techniques and debugging. Thus there was always a range of potential computer applications which were relegated to manual or pocket calculator solutions.

IBM PC Communications

This section outlines the basic principles of serial communications and covers the following areas: i Data communications ii Add-in modems iii Data encryption iv Videotex vi Special purpose.