A dialog-based architecture for interactive information systems

Abstract

Interactive systems may be defined as having the following behavior: a) the user's request is processed as soon as it is received and b) the result is presented to the user on the same medium, i.e. the screen, as soon as it is available. Interactive Information Systems (IIS), identify those systems often encountered in the business world, which consist of many input-output operations and little, simple processing. In the past few years, interest for IIS has been growing (see JAC 83, MAS83, DRA84): the man-machine interface has received special attention, due to the profile of the user who is not a computer specialist. Very few attempts however, have been made to design an architecture for this class of systems, although their characteristics have definite general design consequences. In this article, we will start by investigating the characteristics of IIS. A presentation of ISA (Interactive System Architecture) will follow, showing the main features of the proposed model. The discussion will then concentrate on the use of finite state machines and on the limitations of ISA.