National Academies Press: OpenBook
Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
×

Computers at Risk

Safe Computing In the Information Age

System Security Study Committee

Computer Science and Telecommunications Board

Commission on Physical Sciences, Mathematics, and Applications

National Research Council

NATIONAL ACADEMY PRESS
1991

Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
×

National Academy Press
2101 Constitution Avenue, N.W. Washington, D.C. 20418

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.

This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Frank Press is president of the National Academy of Sciences.

The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Robert M. White is president of the National Academy of Engineering.

The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Samuel O. Thier is president of the Institute of Medicine.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Frank Press and Dr. Robert M. White are chairman and vice chairman, respectively, of the National Research Council.

Support for this project was provided by the Defense Advanced Research Projects Agency under Contract No. N00014-89-J-1731. However, the content does not necessarily reflect the position or the policy of the Defense Advanced Research Projects Agency or the government, and no official endorsement should be inferred.

Library of Congress Cataloging-in-Publication Data

Computers at risk: safe computing in the information age / System Security Study Committee, Computer Science and Telecommunications Board, Commission on Physical Sciences, Mathematics, and Applications, National Research Council.

p. cm.

Includes bibliographical references.

ISBN 0-309-04388-3

1. Computer security. I. National Research Council (U.S.).

Computer Science and Telecommunications Board. System Security Study Committee.

QA76.9.A25C6663 1990

005.8—dc20 90-22329

CIP

Copyright © 1991 by the National Academy of Sciences

No part of this book may be reproduced by any mechanical, photographic, or electronic process, or in the form of a phonographic recording, nor may it be stored in a retrieval system, transmitted, or otherwise copied for public or private use, without written permission from the publisher, except for the purposes of official use by the U.S. government.

Printed in the United States of America

First Printing, December 1990

Second Printing, March 1991

Third Printing, April 1992

Fourth Printing, January 1992

Fifth Printing, March 1994

Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
×

SYSTEM SECURITY STUDY COMMITTEE

DAVID D. CLARK,

Massachusetts Institute of Technology,

Chairman

W. EARL BOEBERT,

Secure Computing Technology Corporation

SUSAN GERHART,

Microelectronics and Computer Technology Corporation

JOHN V. GUTTAG,

Massachusetts Institute of Technology

RICHARD A. KEMMERER,

University of California at Santa Barbara

STEPHEN T. KENT,

BBN Communications

SANDRA M. MANN LAMBERT,

Security Pacific Corporation

BUTLER W. LAMPSON,

Digital Equipment Corporation

JOHN J. LANE,

Shearson, Lehman, Hutton, Inc.

M. DOUGLAS McILROY,

AT&T Bell Laboratories

PETER G. NEUMANN,

SRI International

MICHAEL O. RABIN,

Harvard University

WARREN SCHMITT,

Sears Technology Services

HAROLD F. TIPTON,

Rockwell International

STEPHEN T. WALKER,

Trusted Information Systems, Inc.

WILLIS H. WARE,

The RAND Corporation

MARJORY S. BLUMENTHAL, Staff Director

FRANK PITTELLI, CSTB Consultant

DAMIAN M. SACCOCIO, Staff Officer

MARGARET A. KNEMEYER, Staff Associate

DONNA F. ALLEN, Administrative Secretary

CATHERINE A. SPARKS, Senior Secretary

Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
×

COMPUTER SCIENCE AND TELECOMMUNICATIONS BOARD

JOSEPH F. TRAUB,

Columbia University,

Chairman

ALFRED V. AHO,

AT&T Bell Laboratories

JOHN SEELY BROWN,

Xerox Corporation Palo Alto Research Center

FRANK P. CARRUBBA,

Hewlett-Packard Company

DAVID J. FARBER,

University of Pennsylvania

SAMUEL H. FULLER,

Digital Equipment Corporation

JAMES FREEMAN GILBERT,

University of California at San Diego

WILLIAM A. GODDARD III,

California Institute of Technology

JOHN L. HENNESSY,

Stanford University

JOHN E. HOPCROFT,

Cornell University

MITCHELL D. KAPOR,

ON Technology, Inc.

SIDNEY KARIN,

San Diego Supercomputer Center

LEONARD KLEINROCK,

University of California at Los Angeles

ROBERT LANGRIDGE,

University of California at San Francisco

ROBERT L. MARTIN,

Bell Communications Research

WILLIAM F. MILLER,

SRI International

ABRAHAM PELED,

IBM T.J. Watson Research Center

RAJ REDDY,

Carnegie Mellon University

JEROME H. SALTZER,

Massachusetts Institute of Technology

MARY SHAW,

Carnegie Mellon University

ERIC E. SUMNER,

Institute of Electrical and Electronics Engineers

IVAN E. SUTHERLAND,

Sutherland, Sproull & Associates

GEORGE L. TURIN,

Teknekron Corporation

VICTOR VYSSOTSKY,

Digital Equipment Corporation

WILLIS H. WARE,

The RAND Corporation

WILLIAM WULF,

University of Virginia

MARJORY S. BLUMENTHAL, Staff Director

ANTHONY M. FORTE, Senior Staff Officer

HERBERT LIN, Staff Officer

DAMIAN M. SACCOCIO, Staff Officer

RENEE A. HAWKINS, Staff Associate

DONNA F. ALLEN, Administrative Secretary

LINDA L. JOYNER, Project Assistant

CATHERINE A. SPARKS, Senior Secretary

Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
×

COMMISSION ON PHYSICAL SCIENCES, MATHEMATICS, AND APPLICATIONS*

NORMAN HACKERMAN,

Robert A. Welch Foundation,

Chairman

PETER J. BICKEL,

University of California at Berkeley

GEORGE F. CARRIER,

Harvard University

HERBERT D. DOAN,

The Dow Chemical Company

(retired)

DEAN E. EASTMAN,

IBM T.J. Watson Research Center

MARYE ANNE FOX,

University of Texas

PHILLIP A. GRIFFITHS,

Duke University

NEAL F. LANE,

Rice University

ROBERT W. LUCKY,

AT&T Bell Laboratories

CHRISTOPHER F. McKEE,

University of California at Berkeley

RICHARD S. NICHOLSON,

American Association for the Advancement of Science

JEREMIAH P. OSTRIKER,

Princeton University Observatory

ALAN SCHRIESHEIM,

Argonne National Laboratory

ROY F. SCHWITTERS,

Superconducting Super Collider Laboratory

KENNETH G. WILSON,

Ohio State University

NORMAN METZGER, Executive Director

*  

The project that is the subject of this report was initiated under the predecessor group of the Commission on Physical Sciences, Mathematics, and Applications, which was the Commission on Physical Sciences, Mathematics, and Resources, whose members are listed in Appendix G.

Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
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×

Preface

The Computer Science and Technology Board, which became the Computer Science and Telecommunications Board in September 1990, formed the System Security Study Committee in response to a fall 1988 request from the Defense Advanced Research Projects Agency (DARPA) to address the security and trustworthiness of U.S. computing and communications systems. The committee was charged with developing a national research, engineering, and policy agenda to help the United States achieve a more trustworthy computing technology base by the end of the century. DARPA asked the committee to take a broad outlook—to consider the interrelationship of security and other qualities (e.g., safety and reliability), commercialization as well as research, and the diverse elements of the research and policy communities. In keeping with DARPA's initial request, the committee focused on security aspects but related them to other elements of trustworthiness.

The System Security Study Committee was composed of sixteen individuals from industry and academia, including computer and communications security researchers and practitioners and software engineers. It met in May, August, and November of 1989 and in February, April, and July of 1990. Its deliberations were complemented by briefings from and interviews with a variety of federal government researchers and officials and security experts and others from industry. A central feature of the committee's work was the forging of a consensus in the face of different technical and professional perspectives. While the committee drew on both the research literature and publications aimed at security practitioners, it sought to combine the research and practitioner perspectives to provide a more unified as-

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sessment than might perhaps be typical. Given the goal of producing an unclassified report, the committee focused on the protection of sensitive but unclassified information in computer and communications systems. The orientation toward an unclassified report also limited the extent to which the committee could probe tensions in federal policy between intelligence-gathering and security-providing objectives.

This report of the System Security Study Committee presents its assessment of key computer and communications security issues and its recommendations for enhancing the security and trustworthiness of the U.S. computing and communications infrastructure.

David D. Clark, Chairman

System Security Study Committee

Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
×

Acknowledgments

The System Security Study Committee appreciates the generous assistance provided by Carl Landwehr of the Naval Research Laboratory and a group of federal liaisons that he coordinated, including Anthony Adamski of the Federal Bureau of Investigation, Dennis Branstad of the National Institute of Standards and Technology, Leon Breault of the Department of Energy, Richard Carr of the National Aeronautics and Space Administration, Richard DeMillo of the National Science Foundation (preceded by John Gannon), C. Terrance Ireland of the National Security Agency, Stuart Katzke of the National Institute of Standards and Technology, Robert Morris of the National Security Agency, Karen Morrissette of the Department of Justice, Mark Scher of the Defense Communications Agency, and Kermith Speierman of the National Security Agency. These individuals made themselves and their associates available to the committee to answer questions, provide briefings, and supply valuable reference materials.

The committee is grateful for special briefings provided by William Vance of IBM, John Michael Williams of Unisys, and Peter Wild of Coopers and Lybrand. Additional insight into specific issues was provided by several individuals, including in particular Mark Anderson of the Australian Electronics Research Laboratory, Carolyn Conn of GE Information Services, Jay Crawford of the Naval Weapons Center at China Lake, California, George Dinolt of Ford Aerospace Corporation, Morrie Gasser and Ray Modeen of Digital Equipment Corporation, James Giffin of the Federal Trade Commission, J. Thomas Haigh of Secure Computing Technology Corporation, James Hearn of the National Security Agency, Frank Houston of the Food and Drug Administration, Christian Jahl of the German Industrie Anlagen Betriebs

Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
×

Gesellschaft, Ian King of the U.K. Communications-Electronics Security Group, Stewart Kowalski of the University of Stockholm, Milan Kuchta of the Canadian Communications Security Establishment, Timothy Levin of Gemini Computers, Inc., Michael Nash representing the U.K. Department of Trade and Industry, Stephen Purdy and James Bauer of the U.S. Secret Service, John Shore of Entropic Research Laboratory, Inc., Linda Vetter of Oracle Corporation, Larry Wills of IBM, and the group of 30 corporate security officers who participated in a small, informal survey of product preferences.

The committee appreciates the encouragement and support of Stephen Squires and William Scherlis of DARPA, who provided guidance, insights, and motivation. It is particularly grateful for the literally hundreds of suggestions and criticisms provided by the ten anonymous reviewers of an early draft. Those inputs helped the committee to tighten and strengthen its presentation, for which it, of course, remains responsible.

Finally, the committee would like to acknowledge the major contribution that the staff of the Computer Science and Telecommunications Board has made to this report, in particular thanking Marjory Blumenthal, Damian Saccocio, Frank Pittelli, and Catherine Sparks. They supplied not only very capable administrative support, but also substantial intellectual contributions to the development of the report. The committee also received invaluable assistance from its editor, Susan Maurizi, who labored under tight time constraints to help it express its ideas on a complex and jargon-filled subject. It could not have proceeded effectively without this level of support from the National Research Council.

David D. Clark, Chairman

System Security Study Committee

Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
×
   

Recommendation 5: Fund and Pursue Needed Research,

 

39

   

Recommendation 6: Establish an Information Security Foundation,

 

43

   

Conclusion,

 

45

   

Notes,

 

45

2

 

CONCEPTS OF INFORMATION SECURITY

 

49

   

Security Policies—Responding to Requirements for Confidentiality, Integrity, and Availability,

 

52

   

Confidentiality,

 

52

   

Integrity,

 

54

   

Availability,

 

54

   

Examples of Security Requirements for Different Applications,

 

55

   

Management Controls—Choosing the Means to Secure Information and Operations,

 

56

   

Preventing Breaches of Security—Basic Principles,

 

56

   

Responding to Breaches of Security,

 

59

   

Developing Policies and Appropriate Controls,

 

59

   

Risks and Vulnerabilities,

 

61

   

Securing the Whole System,

 

65

   

Appendix 2.1—Privacy,

 

66

   

Appendix 2.2—Informal Survey to Assess Security Requirements,

 

69

   

Notes,

 

72

3

 

TECHNOLOGY TO ACHIEVE SECURE COMPUTER SYSTEMS

 

74

   

Specification vs. Implementation,

 

75

   

Specification: Policies, Models, and Services,

 

76

   

Policies,

 

77

   

Models,

 

80

   

Flow Model,

 

80

   

Access Control Model,

 

81

   

Services,

 

83

   

Authentication,

 

84

   

Authorization,

 

87

   

Auditing,

 

88

   

Implementation: The Trusted Computing Base,

 

88

   

Computing,

 

91

   

Hardware,

 

91

   

Operating System,

 

92

   

Applications and the Problem of Malicious Code,

 

93

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Communications,

 

93

   

Secure Channels,

 

94

   

Authenticating Channels,

 

96

   

Security Perimeters,

 

98

   

Methodology,

 

99

   

Conclusion,

 

99

   

Notes,

 

100

4

 

PROGRAMMING METHODOLOGY

 

102

   

Software Is More Than Code,

 

104

   

Simpler Is Better,

 

106

   

The Role of Programming Languages,

 

107

   

The Role of Specifications,

 

108

   

Relating Specifications to Programs,

 

109

   

Formal Specification and Verification,

 

111

   

Hazard Analysis,

 

113

   

Structuring the Development Process,

 

114

   

Managing Software Procurement,

 

115

   

Scheduling Software Development,

 

116

   

Education and Training,

 

117

   

Management Concerns in Producing Secure Software,

 

118

   

What Makes Secure Software Different,

 

119

   

Recommended Approaches to Sound Development Methodology,

 

120

   

Notes,

 

122

5

 

CRITERIA TO EVALUATE COMPUTER AND NETWORK SECURITY

 

124

   

Security Evaluation Criteria in General,

 

125

   

Security Characteristics,

 

125

   

Assurance Evaluation,

 

127

   

Trade-offs in Grouping of Criteria,

 

130

   

Comparing National Criteria Sets,

 

133

   

Reciprocity Among Criteria Sets,

 

135

   

System Certification vs. Product Evaluation,

 

137

   

Recommendations for Product Evaluation and System Certification Criteria,

 

139

   

Notes,

 

141

6

 

WHY THE SECURITY MARKET HAS NOT WORKED WELL

 

143

   

The Market for Trustworthy Systems,

 

143

   

A Soft Market: Concerns of Vendors,

 

146

Suggested Citation:"Front Matter." National Research Council. 1991. Computers at Risk: Safe Computing in the Information Age. Washington, DC: The National Academies Press. doi: 10.17226/1581.
×
   

Federal Government Influence on the Market,

 

149

   

Procurement,

 

149

   

Strategic Federal Investments in Research and Development,

 

150

   

Export Controls as a Market Inhibitor,

 

152

   

Technology Transfer: Rationale for Controlling Security Exports,

 

153

   

Export Control of Cryptographic Systems and Components,

 

154

   

Export Control of Trusted Systems,

 

156

   

The Commercial Imperative,

 

157

   

Consumer Awareness,

 

159

   

Insurance as a Market Lever,

 

161

   

Education and Incident Tracking for Security Awareness,

 

162

   

Education,

 

162

   

Incident Reporting and Tracking,

 

163

   

Technical Tools to Compensate for Limited Consumer Awareness,

 

164

   

Regulation as a Market Influence: Product Quality and Liability,

 

165

   

Product Quality Regulations,

 

166

   

Product Liability as a Market Influence,

 

167

   

Software and Systems Present Special Problems,

 

170

   

Toward Equitable Allocation of Liability,

 

171

   

Appendix 6.1— Export Control Process,

 

173

   

Appendix 6.2— Insurance,

 

174

   

Notes,

 

176

7

 

THE NEED TO ESTABLISH AN INFORMATION SECURITY FOUNDATION

 

179

   

Actions Needed to Improve Computer Security,

 

179

   

Attributes and Functions of the Proposed New Institution,

 

180

   

Other Organizations Cannot Fulfill ISF's Mission,

 

183

   

Government Organizations,

 

183

   

Private Organizations,

 

184

   

Why ISF's Mission Should Be Pursued Outside of the Government,

 

185

   

A New Not-for-profit Organization,

 

186

   

Critical Aspects of an ISF Charter,

 

187

   

Start-up Considerations,

 

188

   

Funding the ISF,

 

188

   

Alternatives to the ISF,

 

190

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Computers at Risk presents a comprehensive agenda for developing nationwide policies and practices for computer security. Specific recommendations are provided for industry and for government agencies engaged in computer security activities.

The volume also outlines problems and opportunities in computer security research, recommends ways to improve the research infrastructure, and suggests topics for investigators.

The book explores the diversity of the field, the need to engineer countermeasures based on speculation of what experts think computer attackers may do next, why the technology community has failed to respond to the need for enhanced security systems, how innovators could be encouraged to bring more options to the marketplace, and balancing the importance of security against the right of privacy.

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