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The Internet's Coming of Age (2001)

Chapter: Front Matter

Suggested Citation:"Front Matter." National Research Council. 2001. The Internet's Coming of Age. Washington, DC: The National Academies Press. doi: 10.17226/9823.
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Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

HE INTERNET' COIN Committee on the Internet in the Evolving Information Infrastructure OF AN Computer Science and Telecommunications Board Commission on Physical Sciences, Mathematics, and Applications National Research Council NATIONAL ACADEMY PRESS Washington, D.C.

NOTICE: The project that is the subject of this report was approved by the Gov- erning Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engi- neering, 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. Support for this project was provided by the National Science Foundation under contract No. ANI-9714374. Any opinions, findings, conclusions, or recommenda- tions expressed in this material are those of the authors and do not necessarily reflect the views of the sponsor. Library of Congress Cataloging-in-Publication Data The Internet's coming of age / Committee on the Internet in the Evolving Information Infrastructure, Computer Science and Telecommunications Board, Commission on Physical Sciences, Mathematics, and Applications, National Research Council. p. cm. ISBN 0-309-06992-0 1. Internet. I. National Research Council (U.S.~. Committee on the Internet in the Evolving Information Infrastructure. II. Title. TK5105.875.I57 15435 2000 004.67'8 dc21 00-012242 Additional copies of this report are available from: National Academy Press 2101 Constitution Ave., NW Box 285 Washington, DC 20055 800-624-6242 202-334-3313 (in the Washington metropolitan area) http: / /www.nap.edu Copyright 2001 by the National Academy of Sciences. All rights reserved. Printed in the United States of America

National Acaclemy of Sciences National Acaclemy of Engineering Institute of Meclicine National Research Council The National Academy of Sciences is a private, nonprofit, self-perpetuating soci- ety of distinguished scholars engaged in scientific and engineering research, dedi- cated 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. Bruce M. Alberts 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 mem- bers, sharing with the National Academy of Sciences the responsibility for advis- ing 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. William A. Wulf 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. Kenneth I. Shine is president of the Institute of Medicine. The National Research Council was organized by the National Academy of Sci- ences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal gov- ernment. 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 pro- viding 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. Bruce M. Alberts and Dr. William A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

Prepublication Copy - Subject to Further Editorial Correction Front21-edits_4.doc 10/02/00 4:53 PM P-4 COMMITTEE ON THE INTERNET IN THE EVOLVING INFORMATION INFRASTRUCTURE ERIC SCHMIDT, Novell ~c., Chair TERRENCE McGARTY, The Telmarc Group, Vice-chair ANTHONY S. ACAMPORA, University of California at San Diego WALTER S. BAER, RAND Corporation FRED BAKER, Cisco Systems ANDREW BLAU, Flanerie Works DEBORAH ESTRTN, University of California at Los Angeles CHRISTIAN HUITEMA, Microsoft EDWARD JUNG, INTELLECTUAL VENTURES DAVID A. KETTLER, BelISouth JOHN C. KLENSIN, AT&T MILO MEDIN, Excite@,Home CRAIG PARTRIDGE, BEN Technologies DANIEL SCHUTZER, Citibank Special Advisor DAVID D. CLARK, Massachusetts Institute of Technology Staff JON EISENBERG, Study Director MARJORY S. BLUMENTHAL, Director SUZANNE OSSA, Senior Project Assistant DAVID PADGHAM, Project Assistant

COMMITTEE ON THE INTERNET IN THE EVOLVING INFORMATION INFRASTRUCTURE ERIC SCHMIDT, Novell Inc., Chair TERRENCE McGARTY, The Telmarc Group, Vice Chair ANTHONY S. ACAMPORA, University of California at San Diego WALTER S. BAER, RAND Corporation FRED BAKER, Cisco Systems ANDREW BLAU, Flanerie Works DEBORAH ESTRIN, University of California at Los Angeles CHRISTIAN HUITEMA, Microsoft EDWARD rUNG, Intellectual Ventures DAVID A. KETTLER, BellSouth rOHN C. KLENSIN, AT&T MILO MEDIN, Excite@Home CRAIG PARTRIDGE, BBN Technologies DANIEL SCHUTZER, Citibank Special Advisor DAVID D. CLARK, Massachusetts Institute of Technology Staff rON EISENBERG, Study Director MARrORY S. BLUMENTHAL, Director SUZANNE OSSA, Senior Project Assistant DAVID PADGHAM, Research Assistant v

COMPUTER SCIENCE AND TELECOMMUNICATIONS BOARD DAVID D. CLARK, Massachusetts Institute of Technology, Chair DAVID BORTH, Motorola Labs TAMES CHIDDIX, Time Warner Cable rOHN M. CIOFFI, Stanford University ELAINE COHEN, University of Utah W. BRUCE CROFT, University of Massachusetts, Amherst SUSAN L. GRAHAM, University of California at Berkeley rUDITH HEMPEL, University of California at San Francisco JEFFREY M. JAFFE, IBM Corporation ANNA KARLIN, University of Washington MICHAEL KATZ, University of California at Berkeley BUTLER W. LAMPSON, Microsoft Corporation EDWARD D. LAZOWSKA, University of Washington DAVID LIDDLE, U.S. Venture Partners TOM M. MITCHELL, WhizBang! Labs, Inc. DONALD NORMAN, Unext.com DAVID A. PATTERSON, University of California at Berkeley HENRY (HANK) PERRITT, Chicago-Kent College of Law CHARLES SIMONYI, Microsoft Corporation BURTON SMITH, Tera Computer Company TERRY SMITH, University of California at Santa Barbara LEE SPROULL, New York University MARrORY S. BLUMENTHAL, Director HERBERT S. LIN, Senior Scientist TERRY R. SHEEHAN, Senior Program Officer ALAN S. INOUYE, Senior Program Officer rON EISENBERG, Senior Program Officer GAIL PRITCHARD, Program Officer LYNETTE MILLETT, Program Officer JANET BRISCOE, Administrative Officer DAVID C. DRAKE, Project Assistant DANIEL D. LLATA, Senior Project Assistant MARGARET MARSH, Senior Project Assistant DAVID PADGHAM, Research Assistant MICKELLE RODGERS RODRIGUEZ, Senior Project Assistant SUZANNE OSSA, Senior Project Assistant BRANDYE WILLIAMS, Office Assistant Vl

COMMISSION ON PHYSICAL SCIENCES, MATHEMATICS, AND APPLICATIONS PETER M. BANKS, XR Ventures, LLC, Co-chair WILLIAM H. PRESS, Los Alamos National Laboratory, Co-chair WILLIAM F. BALLHAUS, rR., The Aerospace Corporation SHIRLEY CHIANG, University of California at Davis MARSHALL H. COHEN, California Institute of Technology RONALD G. DOUGLAS, Texas A&M University SAMUEL H. FULLER, Analog Devices, Inc. MICHAEL F. GOODCHILD, University of California at Santa Barbara MARTHA P. HAYNES, Cornell University WESLEY T. HUNTRESS, rR., Carnegie Institution CAROL M. rANTZEN, Westinghouse Savannah River Company PAUL G. KAMINSKI, Technovation, Inc. KENNETH H. KELLER, University of Minnesota rOHN R. KREICK, Sanders, a Lockheed Martin Company (retired) MARSHA I. LESTER, University of Pennsylvania W. CARL LINEBERGER, University of Colorado DUSA M. McDUFF, State University of New York at Stony Brook rANET NORWOOD, Former Commissioner, Bureau of Labor Statistics M. ELISABETH PATE-CORNELL, Stanford University NICHOLAS P. SAMIOS, Brookhaven National Laboratory ROBERT I. SPINRAD, Xerox PARC (retired) TAMES F. HINCHMAN, Acting Executive Director . . v''

Prepublication Copy - Subject to Further Editorial Correction Front21-edits_4.doc 10/02/00 4:53 PM P-8 the Tnternet looks like. This new report gives readers an inside look at today's thriving commercial Internet, identifying short- and long-term technical challenges as well as approaches to Internet-related public policy. The committee wishes to thank the various members ofthe CSTB staff who have helped to make this report happen. In particular, Ion Eisenberg, the stab officer responsible for this project, has played a central role throughout the entire project, coordinating all of the various elements of the report. The committee would also like to thank Suzanne Ossa for her assistance in organizing committee meetings and preparing the report. David Padgham made significant contributions editing and researching this report. Liz Fikre was instrumental in editing the final manuscript. David D. Clark Chair, Computer Science and Telecommunications Board

Preface In 1967, the President's Science Advisory Committee's Panel on Com- puters in Higher Education opened its report by noting that "after grow- ing wildly for years, the field of computing now appears to be approach- ing its infancy.''] This comment preceded by about 2 years the initial deployment of Internet nodes, but while computing developed and pen- etrated society in many ways over the succeeding decades, the Internet grew more slowly until its commercialization in 1995, which led to an explosion of growth that continues today. Extending the 1967 advisory committee's analogy, one might today view the Internet as having reached its adolescence. How it will grow up and how its maturation can be fostered is the subject of this report. Motivated by two concerns what would help the Internet mature to meet ever-rising expectations and how might that maturation be achieved the National Science Foundation asked the Computer Science and Telecommunications Board (CSTB) to undertake a study of the Internet and the key challenges that will shape its maturation, focusing on the core technologies of the Internet. In response to this request, CSTB assembled the Committee on the Internet in the Evolving Information Infrastructure. This committee, made up of experts in technology and President's Science Advisory Committee. 1967. Computers in Higher Education. White House, Washington, D.C., February, p. 1. 1 ~

x PREFACE policy, received briefings and conducted deliberations over a period of almost 2 years. Those 2 years were particularly turbulent. They wit- nessed enormous growth and diversification of the industries and non- profit entities associated with the Internet and turned it into a cause celebre: the Internet seems to be everyone's business today. No matter how rapid the changes, the committee process does not lend itself to the reaching of consensus in "Internet time." Like most CSTB committees, this one, too, needed time to learn, deliberate, and converge and also to see which trends endured and which seemed tran- sient. Many parts of the report required little updating in the course of this work, as they speak to basic design or technical principles that have remained durable. But some elements in the landscape changed over the past year, and the committee strove to update its analysis accordingly. It sought to focus on guiding principles rather than on the more rapidly shifting details. The resulting integrated discussion and analysis is in- tended to help inform technical design, development, deployment, opera- tion, and management decisions relevant to the evolving network of net- works. It is also intended to guide policy makers as they seek to reconcile the Internet's unique features with the existing body of policies and prac- tices that are touched by the Internet, such as telecommunications regula- tion. The Internet's Coming of Age is the latest report in an influential series about the Internet issued by CSTB. The first report, Toward a National Research Network (1988), validated the concept of a comprehensive net- work to support communications among researchers across the country (and around the world), and it leveraged federal funding to support Internet research, development, and deployment in the late 1980s. The second, Realizing the Information Future: The Internet and Beyond (1994), addressed the Internet's transition from a network complex aimed at the research, education, and library communities to a complex serving all segments of the economy and society, noting potential impacts on those pioneering communities and covering a range of issues, from pricing to intellectual property protection, that would impinge on the commercial Internet. It explained the makeup of the Internet, relating its essential technology to the proliferation of uses and communications modes that accelerated in the l990s. The third, The Unpredictable Certainty: Information Infrastructure Through 2000 (1996), examined the different industries whose investments would be key to the Internet's growth and the evolu- tion of user interests in Internet capabilities the chemistry of supply and demand that would shape what the Internet looks like. This new report gives readers an inside look at today's thriving commercial Internet, iden-

PREFACE Xl i tifying short- and long-term technical challenges as well as approaches to Internet-related public policy. The committee wishes to thank the various members of the CSTB staff who helped to make this report happen. In particular, Ton Eisenberg, the staff officer responsible for this project, has played a central role through- out the entire project, coordinating all of the various elements of the re- port. The committee would also like to thank Suzanne Ossa for her assis- tance in organizing committee meetings and preparing the report. David Padgham contributed significantly to the editing and research done for this report. Liz Fikre was instrumental in editing the final manuscript. David D. Clark, Chair Computer Science and Telecommunications Board

Prepublication Copy - Subject to Further Editorial Correction Front 4.doc 10/02/00 4:53 PM P-12 Openness and Innovation Cnbcal Open Standards in the Internet- The Hourglass Architecture The Inte~net as A Platform for Application Innovation Evolution of Internet Standards Setting End-to-End Transparency Addressing Issues Nonuniform Treatment of Bits Market/Business influences on Openness Keeping the Internet Open 4 COLLISIONS BETWEEN EXISTING INDUSTRIES AND EMERGING INTERNET INDUSTRIES: TELEPHONY AS A CASE STUDY Introduction What Is IP Telephony? New and Evolving Architectures for Telephony IP Telephony Architectures The Evolving Architecture of the PSTN Architectural Contrasts Between IP Telephony and Today's PSTN Scenarios for Future Evolution Interoperation between IP Telephony and the PSTN Addressing and Number Portability Signaling and Control and Service Creation Robustness Considerations Implications of IP Telephony for Telephony Regulation Looking Forward: The Internet and Other Industry Sectors 5 IMPLICATIONS FOR BROAD PUBLIC POLICY Introduction Privacy, Anonymity, and Identity Privacy Anonymity Identity Authentication on the Internet Taxation of Internet-based Commerce Universal Service APPENDIX: BIOGRAPHIES OF COMMEl~l BE MEMBERS

Acknowledgmen! of Reviewers This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with pro- cedures approved by the NRC's Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integ- rity of the deliberative process. We wish to thank the following individu- als for their review of this report: Geoff Baehr, Sun Microsystems, Inc., Edward Balkovich, Bell Atlantic, Scott Bradner, Harvard University, Hans-Werner Braun, University of California at San Diego, Charles N. Brownstein, Corporation for National Research Initiatives, Brian E. Carpenter, IBM, William J. Dally, Stanford University, Joseph Farrell, University of California at Berkeley, Robert M. Frieden, Pennsylvania State University, Reed E. Hundt, McKinsey & Company, Geoffrey Huston, Telstra Internet, Stephen T. Kent, BEN Corporation, Hal Varian, University of California at Berkeley, and Kevin Werbach, Release 1.0. . . . x'''

xIv ACKNOWLEDGMENT OF REVIEWERS Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclu- sions or recommendations, nor did they see the final draft of the report before its release. The review of this report was overseen by William H. Press, Los Alamos National Laboratory, appointed by the NRC's Com- mission on Physical Sciences, Mathematics, and Applications, who was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.

ConIenis OVERVIEW AND RECOMMENDATIONS 1 INTRODUCTION AND CONTEXT What Is the Internet?, 29 Success by Design Abstract Features and Principles, 34 The Internet's "Hourglass" Architecture, 36 The Robustness Principle, 39 Scalable, Distributed, and Adaptive Design, 40 From Internet Technology to Internet Marketplace, 41 Internet Organizations, 43 Key Trends in Internet Development, 44 Growth in Backbone Capacity, 45 Growth and Diversification of the ISP Market, 46 Upgrading the Local Access Infrastructure, 46 Growing Role for Wireless Services, 49 Voice and Data Services, 50 Rise in the Use of Single-Purpose Devices, 50 Future Evolution and Success, 51 2 SCALING UP THE INTERNET AND MAKING IT MORE RELIABLE AND ROBUST Building a Better Internet, 53 Scaling, 54 Scaling of Capacity, 55 xv 1 29 53

xv! CONTENTS Scaling of Protocols and Algorithms, 56 Scaling of the Internet's Naming Systems, 58 Scaling up the Address Space, 64 Managing Addresses, 65 Routing Table Scaling and Address Aggregation, 66 Running Out of Addresses?, 71 Network Address Translation, 76 IPv6: A Potential Solution to Addressing and Configuration, 77 Deploying an IPv6 Solution, 79 Reliability and Robustness, 81 Designing for Robustness and Reliability, 82 Vulnerability of the Internet to Attack, 84 More Adaptive Routing, 89 Putting It Together, 90 Application Reliability and Robustness, 92 Robustness and Auxiliary Servers, 93 Toward Greater Reliability and Robustness: Reporting Outages and Failures, 94 Quality of Service, 98 3 KEEPING THE INTERNET THE INTERNET: INTERCONNECTION, OPENNESS, AND TRANSPARENCY 107 Interconnection: Maintaining End-to-End Service Through Multiple Providers, 107 Structure of the Internet Service Provider Industry, 109 Interconnection Mechanisms and Agreements, 112 Considerations Affecting Decisions to Enter into Peering Agreements, 118 Evolution of Interconnection Models, 121 Monitoring Internet Interconnection, 123 Openness and Innovation, 124 Critical Open Standards in the Internet The Hourglass Architecture, 126 The Internet As a Platform for Application Innovation, 131 Evolution of Internet Standards Setting, 132 End-to-End Transparency, 138 Addressing Issues, 139 Nonuniform Treatment of Bits, 142 Market and Business Influences on Openness, 145 Keeping the Internet Open, 149

CONTENTS 4 COLLISIONS BETWEEN EXISTING INDUSTRIES AND EMERGING INTERNET INDUSTRIES: TELEPHONY AS A CASE STUDY Introduction, 151 What Is IP Telephony?, 152 New and Evolving Architectures for Telephony, 154 IP Telephony Architectures, 155 The Evolving Architecture of the PSTN, 159 Architectural Contrasts Between IP Telephony and Today's PSTN, 161 Scenarios for Future Evolution, 162 Interoperation Between IP Telephony and the PSTN, 165 Addressing and Number Portability, 167 Signaling and Control and Service Creation, 168 Robustness, 169 Implications of IP Telephony for Telephony Regulation, 170 Looking Forward: The Internet and Other Industry Sectors, 175 5 IMPLICATIONS FOR BROAD PUBLIC POLICY Introduction, 177 Privacy, Anonymity, and Identity, 180 Privacy, 180 Anonymity, 190 Identity, 194 Authentication on the Internet, 199 Taxation of Internet-based Commerce, 205 Universal Service, 209 . . XVII 151 177 APPENDIX: BIOGRAPHIES OF COMMITTEE MEMBERS 217 INDEX 225

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What most of us know as "the Internet" is actually a set of largely autonomous, loosely coordinated communication networks. As the influence of the Internet continues to grow, understanding its real nature is imperative to acting on a wide range of policy issues.

This timely new book explains basic design choices that underlie the Internet's success, identifies key trends in the evolution of the Internet, evaluates current and prospective technical, operational, and management challenges, and explores the resulting implications for decision makers. The committee-composed of distinguished leaders from both the corporate and academic community-makes recommendations aimed at policy makers, industry, and researchers, going on to discuss a variety of issues:

  • How the Internet's constituent parts are interlinked, and how economic and technical factors make maintaining the Internet's seamless appearance complicated.
  • How the Internet faces scaling challenges as it grows to meet the demands of users in the future.
  • Tensions inherent between open innovation on the Internet and the ability of innovators to capture the commercial value of their breakthroughs.
  • Regulatory issues posed by the Internet's entry into other sectors, such as telephony.
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