The concept of reengineering, as popularized by Champy and Hammer (1993), relies on ubiquitous access to corporate data. Also, reengineering focuses on how the processes of an organization can be modified, to capitalize on this ubiquitous data access, to be significantly more productive. These two features of their program, while often put to good use by corporate executives, have perplexed many information system managers who have tried to reap similar benefits by reengineering their information systems. The paper discusses architectural issues that arise from the reengineering process and what types of architectures survive this process in the most painless way.

A discussion is given on whether the Ada model of concurrency is suitable for implementing the seven-layer OSI reference model. Using the communications model introduced by R.J.A. Buhr (1984), they determine the overhead introduced by Ada when the model is implemented on two single-processor machines, a VAX 11/785 and a Rational 1000. The authors then calculate a lower bound on expected message delay. A novel model using server tasks is proposed and shown to have better performance. The authors investigate performance on an eight-processor Sequent Model 821 and a 14-processor Encore Multimax 320 by implementing the Buhr model, the server task model and a third model which abandons the Ada rendezvous in favor of procedure calls. They determine the Ada overhead per message as a function of the number of processors and calculate lower bounds on expected message delay attributable to Ada overhead for all three communications models.>

In the area of software development, data processing management often focuses more on coding techniques and system architecture than on how to manage the development. In recent years, ``structured programming'' and ``structured analysis'' have received more attention than the techniques software managers employ to manage. Moreover, these coding and architectural considerations are often advanced as the key to a smooth running, well managed project. This paper documents a philosophy for software development and the tools used to support it. Those management techniques deal with quantifying such abstract terms as ``productivity,'' ``performance,'' and ``progress,'' and with measuring these quantities and applying management controls to maximize them. The paper also documents the application of these techniques on a major software development effort.