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Time and time again software projects, though undertaken by people of considerable intellectual ability, fail. This will doubtless be a continuing phenomenon, because software production is indeed a difficult task requiring wide-ranging skills. Certainly, no single paper can suddenly solve all the problems of software writing and eliminate the failures. The scope of this paper is limited to four stages in the execution of software projects, namely the planning, coding, testing, and final usage. These four crucial areas contain pitfalls that have been responsible for a large proportion of software failures, and it is hoped this paper will help avoid some of them. [ABSTRACT FROM AUTHOR]

The concept of "process" has come to play a central role in many efforts to master the complexity of large computer systems. The purpose of this paper is to discuss useful methods of structuring complex processes, and to relate these to the problems of improving the quality of large computer systems. Two distinct ways of structuring systems are presented, namely, process combination, and process abstraction; these are then used to discuss such topics as concurrency, synchronization, multiprogramming, interpreters, and programmable processors. This discussion is based on a set of precise definitions for such concepts as "process," "processor," "computation," "combination," and "abstraction." The paper relates these definitions to both current research and practical applications, with particular concern for the problems of the performance, reliability, and modifiability of computer systems. [ABSTRACT FROM AUTHOR]

This paper is a tutorial on the methods used to control the transmission of digital information on data communication links. Simple models of data communication systems are introduced and terminology for describing their functions and operation is established. Various graphical methods of representing communication control procedures are discussed and used to describe significant features of communication control procedures in detail. [ABSTRACT FROM AUTHOR]

The bibliography appearing at the end of this article lists 37 sorting algorithms and 100 books and papers on sorting published in the last 20 years. The basic ideas presented here have been abstracted from this body of work, and the best algorithms known are given as examples. As the algorithms are explained, references to related algorithms and mathematical or experimental analyses are given. Suggestions are then made for choosing the algorithm best suited to a given situation. [ABSTRACT FROM AUTHOR]

This is a tutorial paper describing the construction of a basic simulation model for a disk-based multiprogrammed computer system. First, the job processing sequence of the system to be simulated is described and techniques for generating the simulated job mix are discussed. The structure of simulation models, events, and events scheduled are then introduced. A simulation model for the multiprogrammed system is presented and the event routines comprising the model are discussed. The use of GPSS, SIMSCRIPT, and FORTRAN in constructing a simulation model is reviewed. [ABSTRACT FROM AUTHOR]