Advertisement

Research and Advances

On the security of multiple encryption

Double encryption has been suggested to strengthen the Federal Data Encryption Standard (DES). A recent proposal suggests that using two 56-bit keys but enciphering 3 times (encrypt with a first key, decrypt with a second key, then encrypt with the first key again) increases security over simple double encryption. This paper shows that although either technique significantly improves security over single encryption, the new technique does not significantly increase security over simple double encryption. Cryptanalysis of the 112-bit key requires about 256 operations and words of memory, using a chosen plaintext attack. While DES is used as an example, the technique is applicable to any similar cipher.
Research and Advances

Response to the Federal Trade Commission’s proposed ruling on standards and certification

In December 1978, the Federal Trade Commission issued a notice of intention of rulemaking in regard to the matter of Standards and Certification. In cooperation with the American National Standards Institute, of which ACM is a member, the ACM Standards Committee prepared a response to that notice and submitted it to the Commission in April 1979. The response gives a summary of the ACM Standards Committee position on a standards regulation and affords insights into the process by which procedures evolve in this area. For this reason, the response is reproduced here as a report.
Opinion

ACM president’s letter: eating our seed corn

On July 12 and 13, 1980, the biennial meeting of Computer Science Department chairmen was held at Snowbird, Utah. This meeting, which is organized by the Computer Science Board (CSB), is a forum for the heads of the 83 departments in the United States and Canada that grant Ph.D.s in Computer Science. The meeting was attended by 56 department heads or their representatives, and by six observers from industry and government. This report was developed during the meeting as a result of intensive discussions about the crisis in Computer Science. This report was endorsed by the entire assembly.
Research and Advances

Quo Vadimus: computer science in a decade

A panel discussion was held during the third biennial meeting of chairmen of Ph.D.-granting computer science departments in June, 1978 at Snowbird, Utah, a meeting sponsored by the Computer Science Board. Invitees from industry and government were also present. A report was prepared from tapes made of the discussion (Department of Computer Science, Carnegie-Mellon University: Report #CMU-CS-80-127, June 1980). It contained all the prepared statements of the panelists, lightly edited, and the panelists' discussion in its entirety. A selection of the audience discussion was also included, rather heavily edited. The following presentation is derived from that report.
Research and Advances

The external auditor’s review of computer controls

The Foreign Corrupt Practices Act of 1977, coupled with growing demands for corporate accountability, have forced both auditors and computer administrators to evaluate computer based controls. Computer administrators can benefit from both a knowledge of an auditor's approaches to evaluating controls and his/her recommendations for control improvements. Here, a survey of the control evaluation practices and desirable control features identified by computer auditors is presented, along with recommendations to ease the burden of the auditor's review. The authors' suggestions should ease the tasks of internal control analysis and of preparation for possible public reports on an organization's system of internal control.
Research and Advances

On approaches to the study of social issues in computing

This paper identifies and analyzes technical and nontechnical biases in research on social issues in computing. Five positions—technicism, progressive individualism, elitism, pluralism, and radical criticism—which reflect major streams of contemporary social thought are examined. The analysis of positions documents the close relationship between research and policy formation and reveals the misleading and dangerous character of the presumption of scholarly objectivity in research on social issues.
Research and Advances

Educational programs in information systems: a report of the ACM curriculum committee on information systems

This report describes the status of educational programs in Information Systems at the B.S., M.S., and Ph.D. levels. A survey was conducted during the period June 1977-June 1979 of schools of Business Administration, Departments of Computer Science, Engineering Colleges, and academic units offering programs in Information Systems. A one-page description of each program was then generated according to a standard format. This standardized description was used as a guide to summarize information about each program. The report outlines career opportunities in Information Systems and lists brief descriptions of positions available to graduates of Information Systems programs. The need for an Information Systems program and problem areas with respect to teaching information systems are discussed. The results of the survey include a listing of the most common names for the Information Systems program and an evaluation of the number of programs that met the guidelines established by the Curriculum Committee on Computer Education for Management in 1972 and 1973. A list of institutions by degree level that met the proposed guidelines is presented.
Research and Advances

The effect of programming team structures on programming tasks

The literature recognizes two group structures for managing programming projects: Baker's chief programmer team and Weinberg's egoless team. Although each structure's success in project management can be demonstrated, this success is clearly dependent on the type of programming task undertaken. Here, for the purposes of comparison, a third project organization which lies between the other two in its communication patterns and dissemination of decision-making authority is presented. Recommendations are given for selecting one of the three team organizations depending on the task to be performed.
Research and Advances

Computer scientists whose scientific freedom and human rights have been violated: a report of the ACM committee on scientific freedom and human rights

This report had its genesis before the establishment in February 1980 of the Committee on Scientific Freedom and Human Rights (CSFHR). In 1978 Paul Armer, chairman of the Committee on Computers and Public Policy (CCPP), asked Jack Minker of the University of Maryland to chair a Subcommittee on Human Rights and to prepare a report on the human rights of computer scientists. When CSFHR was formed it was natural to transfer this activity to it since one of the activities of CSFHR, as specified in its charter, is: Gathering data on systematic violations of scientific freedom and human rights and fully publicizing such data.… Careful attention will be given to assuring the validity of all data.
Research and Advances

Recommendations for master’s level programs in computer science: a report of the ACM curriculum committee on computer science

The ACM Committee on Curriculum in Computer Science has spent two years investigating master's degree programs in Computer Science. This report contains the conclusions of that effort. Recommendations are made concerning the form, entrance requirements, possible courses, staffing levels, intent, library resources, and computing resources required for an academic, professional, or specialized master's degree. These recommendations specify minimum requirements which should be met by any master's programs. The Committee believes that the details of a particular master's program should be determined and continually updated by the faculty involved. A single or a small number of model programs are not as appropriate at the graduate level as at the bachelor's level.
Research and Advances

Using encryption for authentication in large networks of computers

Use of encryption to achieve authenticated communication in computer networks is discussed. Example protocols are presented for the establishment of authenticated connections, for the management of authenticated mail, and for signature verification and document integrity guarantee. Both conventional and public-key encryption algorithms are considered as the basis for protocols.
Research and Advances

A strategic planning methodology for the computing effort in higher education: an empirical evaluation

The findings of a study designed to address the pressing problems associated with the strategic planning of the computing effort in higher education are presented here. A planning methodology was developed and tested through implementation at a university. Two years after the methodology was implemented, the effectiveness of the planning methodology was assessed in terms of the improvement of the delivery of computing services to the major institutional roles of instruction, research, and administration. Two control institutions were employed to contrast the improvements at the test institution. The results of the research indicate the planning methodology significantly enhanced the delivery of computing services.
Research and Advances

Detection of logical errors in decision table programs

In this paper an algorithm to detect logical errors in a limited-entry decision table and in loop-free programs with embedded decision tables is developed. All the conditions in the decision tables are assumed to be inequalities or equalities relating linear expressions. It is also assumed that actions in a decision table are linear in variables which occur in the condition stub of the decision table (or tables) to which control is transferred from the table. The algorithm is based on determining whether a set of linear inequalities has or does not have a solution. The algorithm described in the paper is implemented in Fortran IV.
Research and Advances

Performance evaluation of highly concurrent computers by deterministic simulation

Simulation is presented as a practical technique for performance evaluation of alternative configurations of highly concurrent computers. A technique is described for constructing a detailed deterministic simulation model of a system. In the model a control stream replaces the instruction and data streams of the real system. Simulation of the system model yields the timing and resource usage statistics needed for performance evaluation, without the necessity of emulating the system. As a case study, the implementation of a simulator of a model of the CPU-memory subsystem of the IBM 360/91 is described. The results of evaluating some alternative system designs are discussed. The experiments reveal that, for the case study, the major bottlenecks in the system are the memory unit and the fixed point unit. Further, it appears that many of the sophisticated pipelining and buffering techniques implemented in the architecture of the IBM 360/91 are of little value when high-speed (cache) memory is used, as in the IBM 360/195.

Shape the Future of Computing

ACM encourages its members to take a direct hand in shaping the future of the association. There are more ways than ever to get involved.

Get Involved

Communications of the ACM (CACM) is now a fully Open Access publication.

By opening CACM to the world, we hope to increase engagement among the broader computer science community and encourage non-members to discover the rich resources ACM has to offer.

Learn More