More Advance Praise for Blown to Bits “Most writing about the digital world comes from techies writing about tech- nical matter for other techies or from pundits whose turn of phrase greatly exceeds their technical knowledge. In Blown to Bits , experts in computer science address authoritatively the practical issues in which we all have keen interest.” — Howard Gardner , Hobbs Professor of Cognition and Education, Harvard Graduate School of Education, author of Multiple Intelligences and Changing Minds “Regardless of your experience with computers, Blown to Bits provides a uniquely entertaining and informative perspective from the computing indus- try’s greatest minds. A fascinating, insightful and entertaining book that helps you understand computers and their impact on the world in a whole new way. This is a rare book that explains the impact of the digital explosion in a way that everyone can understand and, at the same time, challenges experts to think in new ways.” — Anne Margulies , Assistant Secretary for Information Technology and Chief Information Officer of the Commonwealth of Massachusetts “ Blown to Bits is fun and fundamental. What a pleasure to see real teachers offering such excellent framework for students in a digital age to explore and understand their digital environment, code and law, starting with the insight of Claude Shannon. I look forward to you teaching in an open online school.” — Professor Charles Nesson , Harvard Law School, Founder, Berkman Center for Internet and Society “To many of us, computers and the Internet are magic. We make stuff, send stuff, receive stuff, and buy stuff. It’s all pointing, clicking, copying, and pasting. But it’s all mysterious. This book explains in clear and comprehen- sive terms how all this gear on my desk works and why we should pay close attention to these revolutionary changes in our lives. It’s a brilliant and nec- essary work for consumers, citizens, and students of all ages.” — Siva Vaidhyanathan, cultural historian and media scholar at the University of Virginia and author of Copyrights and Copywrongs: The Rise of Intellectual Property and How it Threatens Creativity 00_0137135599_FM.qxd 5/7/08 1:00 PM Page i “The world has turned into the proverbial elephant and we the blind men. The old and the young among us risk being controlled by, rather than in control of, events and technologies. Blown to Bits is a remarkable and essential Rosetta Stone for beginning to figure out how all of the pieces of the new world we have just begun to enter—law, technology, culture, information—are going to fit together. Will life explode with new possibilities, or contract under pressure of new horrors? The precipice is both exhilarating and fright- ening. Hal Abelson, Ken Ledeen, and Harry Lewis, together, have ably man- aged to describe the elephant. Readers of this compact book describing the beginning stages of a vast human adventure will be one jump ahead, for they will have a framework on which to hang new pieces that will continue to appear with remarkable speed. To say that this is a ‘must read’ sounds trite, but, this time, it’s absolutely true.” — Harvey Silverglate , criminal defense and civil liberties lawyer and writer 00_0137135599_FM.qxd 5/7/08 1:00 PM Page ii Blown to Bits Your Life, Liberty, and Happiness After the Digital Explosion Hal Abelson Ken Ledeen Harry Lewis Upper Saddle River, NJ • Boston • Indianapolis • San Francisco New York • Toronto • Montreal • London • Munich • Paris • Madrid Cape Town • Sydney • Tokyo • Singapore • Mexico City 00_0137135599_FM.qxd 5/7/08 1:00 PM Page iii Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and the publisher was aware of a trademark claim, the designations have been printed with initial capital letters or in all capitals. The authors and publisher have taken care in the preparation of this book, but make no expressed or implied warranty of any kind and assume no responsibility for errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of the use of the information or programs contained herein. The publisher offers excellent discounts on this book when ordered in quantity for bulk purchases or special sales, which may include electronic versions and/or custom covers and content particular to your business, training goals, marketing focus, and branding interests. For more information, please contact: U.S. Corporate and Government Sales (800) 382-3419 corpsales@pearsontechgroup.com For sales outside the United States, please contact: International Sales international@pearson.com Visit us on the Web: www.informit.com/aw Library of Congress Cataloging-in-Publication Data: Abelson, Harold. Blown to bits : your life, liberty, and happiness after the digital explosion / Hal Abelson, Ken Ledeen, Harry Lewis. p. cm. ISBN 0-13-713559-9 (hardback : alk. paper) 1. Computers and civilization. 2. Information technology—Technological innovations. 3. Digital media. I. Ledeen, Ken, 1946- II. Lewis, Harry R. III. Title. QA76.9.C66A245 2008 303.48’33—dc22 2008005910 Copyright © 2008 Hal Abelson, Ken Ledeen, and Harry Lewis For information regarding permissions, write to: Pearson Education, Inc. Rights and Contracts Department 501 Boylston Street, Suite 900 Boston, MA 02116 Fax (617) 671 3447 00_0137135599_FM.qxd 5/7/08 1:00 PM Page iv This work is licensed under the Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License. To view a copy of this license visit http://creativecommons.org/licenses/by-nc-sa/3.0/us/ or send a letter to Creative Commons 171 Second Street, Suite 300, San Francisco, California, 94105, USA. ISBN-13: 978-0-13-713559-2 ISBN-10: 0-13-713559-9 Text printed in the United States on recycled paper at RR Donnelley in Crawfordsville, Indiana. Third printing December 2008 This Book Is Safari Enabled The Safari ® Enabled icon on the cover of your favorite technology book means the book is available through Safari Bookshelf. When you buy this book, you get free access to the online edition for 45 days. Safari Bookshelf is an electronic reference library that lets you easily search thousands of technical books, find code samples, download chapters, and access technical information whenever and wherever you need it. To gain 45-day Safari Enabled access to this book: • Go to http://www.informit.com/onlineedition • Complete the brief registration form • Enter the coupon code 9SD6-IQLD-ZDNI-AGEC-AG6L If you have difficulty registering on Safari Bookshelf or accessing the online edition, please e-mail customer-service@safaribooksonline.com. Editor in Chief Mark Taub Acquisitions Editor Greg Doench Development Editor Michael Thurston Managing Editor Gina Kanouse Senior Project Editor Kristy Hart Copy Editor Water Crest Publishing, Inc. Indexer Erika Millen Proofreader Williams Woods Publishing Services Publishing Coordinator Michelle Housley Interior Designer and Composition Nonie Ratcliff Cover Designer Chuti Prasertsith 00_0137135599_FM.qxd 11/21/08 10:32 AM Page v 00_0137135599_FM.qxd 5/7/08 1:00 PM Page vi To our children, Amanda, Jennifer, Joshua, Elaheh, Annie, and Elizabeth, who will see the world changed yet again in ways we cannot imagine. 00_0137135599_FM.qxd 5/7/08 1:00 PM Page vii 00_0137135599_FM.qxd 5/7/08 1:00 PM Page viii Contents Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii Chapter 1 Digital Explosion Why Is It Happening, and What Is at Stake? . . . . . . . . . 1 The Explosion of Bits, and Everything Else . . . . . . . . . . 2 The Koans of Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Good and Ill, Promise and Peril . . . . . . . . . . . . . . . . . . 13 Chapter 2 Naked in the Sunlight Privacy Lost, Privacy Abandoned . . . . . . . . . . . . . . . . . . 19 1984 Is Here, and We Like It . . . . . . . . . . . . . . . . . . . . 19 Footprints and Fingerprints . . . . . . . . . . . . . . . . . . . . . 22 Why We Lost Our Privacy, or Gave It Away . . . . . . . . . 36 Little Brother Is Watching . . . . . . . . . . . . . . . . . . . . . . 42 Big Brother, Abroad and in the U.S. . . . . . . . . . . . . . . 48 Technology Change and Lifestyle Change . . . . . . . . . . 55 Beyond Privacy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 Chapter 3 Ghosts in the Machine Secrets and Surprises of Electronic Documents . . . . . . 73 What You See Is Not What the Computer Knows . . . . 73 Representation, Reality, and Illusion . . . . . . . . . . . . . . 80 Hiding Information in Images . . . . . . . . . . . . . . . . . . 94 The Scary Secrets of Old Disks . . . . . . . . . . . . . . . . . . 99 00_0137135599_FM.qxd 5/7/08 1:00 PM Page ix Chapter 4 Needles in the Haystack Google and Other Brokers in the Bits Bazaar . . . . . . . 109 Found After Seventy Years . . . . . . . . . . . . . . . . . . . . 109 The Library and the Bazaar . . . . . . . . . . . . . . . . . . . . 110 The Fall of Hierarchy . . . . . . . . . . . . . . . . . . . . . . . . . 117 It Matters How It Works . . . . . . . . . . . . . . . . . . . . . . 120 Who Pays, and for What? . . . . . . . . . . . . . . . . . . . . . 138 Search Is Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 You Searched for WHAT? Tracking Searches . . . . . . . 156 Regulating or Replacing the Brokers . . . . . . . . . . . . . 158 Chapter 5 Secret Bits How Codes Became Unbreakable . . . . . . . . . . . . . . . . 161 Encryption in the Hands of Terrorists, and Everyone Else . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161 Historical Cryptography . . . . . . . . . . . . . . . . . . . . . . 165 Lessons for the Internet Age . . . . . . . . . . . . . . . . . . . 174 Secrecy Changes Forever . . . . . . . . . . . . . . . . . . . . . 178 Cryptography for Everyone . . . . . . . . . . . . . . . . . . . 187 Cryptography Unsettled . . . . . . . . . . . . . . . . . . . . . . 191 Chapter 6 Balance Toppled Who Owns the Bits? . . . . . . . . . . . . . . . . . . . . . . . . . . 195 Automated Crimes—Automated Justice . . . . . . . . . . . 195 NET Act Makes Sharing a Crime . . . . . . . . . . . . . . . . 199 The Peer-to-Peer Upheaval . . . . . . . . . . . . . . . . . . . . 201 Sharing Goes Decentralized . . . . . . . . . . . . . . . . . . . 204 Authorized Use Only . . . . . . . . . . . . . . . . . . . . . . . . 209 Forbidden Technology . . . . . . . . . . . . . . . . . . . . . . . 213 Copyright Koyaanisqatsi: Life Out of Balance . . . . . . 219 The Limits of Property . . . . . . . . . . . . . . . . . . . . . . . 225 Chapter 7 You Can’t Say That on the Internet Guarding the Frontiers of Digital Expression . . . . . . . 229 Do You Know Where Your Child Is on the Web Tonight? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229 X B L O W N T O B I T S 00_0137135599_FM.qxd 5/7/08 1:00 PM Page x C O N T E N T S XI Metaphors for Something Unlike Anything Else . . . . 231 Publisher or Distributor? . . . . . . . . . . . . . . . . . . . . . 234 Neither Liberty nor Security . . . . . . . . . . . . . . . . . . . 235 The Nastiest Place on Earth . . . . . . . . . . . . . . . . . . . 237 The Most Participatory Form of Mass Speech . . . . . . 239 Protecting Good Samaritans—and a Few Bad Ones . . 242 Laws of Unintended Consequences . . . . . . . . . . . . . . 245 Can the Internet Be Like a Magazine Store? . . . . . . . 247 Let Your Fingers Do the Stalking . . . . . . . . . . . . . . . 249 Like an Annoying Telephone Call? . . . . . . . . . . . . . . 251 Digital Protection, Digital Censorship—and Self- Censorship . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253 Chapter 8 Bits in the Air Old Metaphors, New Technologies, and Free Speech . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 Censoring the President . . . . . . . . . . . . . . . . . . . . . . . 259 How Broadcasting Became Regulated . . . . . . . . . . . . 260 The Path to Spectrum Deregulation . . . . . . . . . . . . . 273 What Does the Future Hold for Radio? . . . . . . . . . . . 288 Conclusion After the Explosion . . . . . . . . . . . . . . . . . . . . . . . . . . . 295 Bits Lighting Up the World . . . . . . . . . . . . . . . . . . . . 295 A Few Bits in Conclusion . . . . . . . . . . . . . . . . . . . . . 299 Appendix The Internet as System and Spirit . . . . . . . . . . . . . . . . 301 The Internet as a Communication System . . . . . . . . . 301 The Internet Spirit . . . . . . . . . . . . . . . . . . . . . . . . . . 309 Endnotes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347 00_0137135599_FM.qxd 5/7/08 1:00 PM Page xi 00_0137135599_FM.qxd 5/7/08 1:00 PM Page xii Preface For thousands of years, people have been saying that the world is changing and will never again be the same. Yet the profound changes happening today are different, because they result from a specific technological development. It is now possible, in principle, to remember everything that anyone says, writes, sings, draws, or photographs. Everything. If digitized, the world has enough disks and memory chips to save it all, for as long as civilization can keep producing computers and disk drives. Global computer networks can make it available to everywhere in the world, almost instantly. And comput- ers are powerful enough to extract meaning from all that information, to find patterns and make connections in the blink of an eye. In centuries gone by, others may have dreamed these things could happen, in utopian fantasies or in nightmares. But now they are happening. We are living in the middle of the changes, and we can see the changes happening. But we don’t know how things will turn out. Right now, governments and the other institutions of human societies are deciding how to use the new possibilities. Each of us is participating as we make decisions for ourselves, for our families, and for people we work with. Everyone needs to know how their world and the world around them is changing as a result of this explosion of digital information. Everyone should know how the decisions will affect their lives, and the lives of their children and grandchildren and everyone who comes after. That is why we wrote this book. Each of us has been in the computing field for more than 40 years. The book is the product of a lifetime of observing and participating in the changes it has brought. Each of us has been both a teacher and a learner in the field. This book emerged from a general education course we have taught at Harvard, but it is not a textbook. We wrote this book to share what wisdom we have with as many people as we can reach. We try to paint a big picture, with dozens of illuminating anecdotes as the brushstrokes. We aim to enter- tain you at the same time as we provoke your thinking. You can read the chapters in any order. The Appendix is a self-contained explanation of how the Internet works. You don’t need a computer to read this book. But we would suggest that you use one, connected to the Internet, 00_0137135599_FM.qxd 5/7/08 1:00 PM Page xiii to explore any topic that strikes your curiosity or excites your interest. Don’t be afraid to type some of the things we mention into your favorite search engine and see what comes up. We mention many web sites, and give their complete descriptors, such as bitsbook.com , which happens to be the site for this book itself. But most of the time, you should be able to find things more quickly by searching for them. There are many valuable public information sources and public interest groups where you can learn more, and can par- ticipate in the ongoing global conversation about the issues we discuss. We offer some strong opinions in this book. If you would like to react to what we say, please visit the book’s web site for an ongoing discussion. Our picture of the changes brought by the digital explosion is drawn largely with reference to the United States and its laws and culture, but the issues we raise are critical for citizens of all free societies, and for all people who hope their societies will become freer. Cambridge, Massachusetts January 2008 X I V B L O W N T O B I T S 00_0137135599_FM.qxd 5/7/08 1:00 PM Page xiv Acknowledgments While we take full responsibility for any errors in the book, we owe thanks to a great many others for any enlightenment it may provide. Specifically, we are grateful to the following individuals, who commented on parts of the book while it was in draft or provided other valuable assistance: Lynn Abelson, Meg Ausman, Scott Bradner, Art Brodsky, Mike Carroll, Marcus Cohn, Frank Cornelius, Alex Curtis, Natasha Devroye, David Fahrenthold, Robert Faris, Johann-Christoph Freytag, Wendy Gordon, Tom Hemnes, Brian LaMacchia, Marshall Lerner, Anne Lewis, Elizabeth Lewis, Jessica Litman, Lory Lybeck, Fred vonLohmann, Marlyn McGrath, Michael Marcus, Michael Mitzenmacher, Steve Papa, Jonathan Pearce, Bradley Pell, Les Perelman, Pamela Samuelson, Jeff Schiller, Katie Sluder, Gigi Sohn, Debora Spar, René Stein, Alex Tibbetts, Susannah Tobin, Salil Vadhan, David Warsh, Danny Weitzner, and Matt Welsh. 00_0137135599_FM.qxd 5/7/08 1:00 PM Page xv 00_0137135599_FM.qxd 5/7/08 1:00 PM Page xvi About the Authors Hal Abelson is Class of 1922 Professor of Computer Science and Engineering at MIT, and an IEEE Fellow. He has helped drive innovative educational tech- nology initiatives such MIT OpenCourseWare, cofounded Creative Commons and Public Knowledge, and was founding director of the Free Software Foundation. Ken Ledeen , Chairman/CEO of Nevo Technologies, has served on the boards of numerous technology companies. Harry Lewis , former Dean of Harvard College, is Gordon McKay Professor of Computer Science at Harvard and Fellow of the Berkman Center for Internet and Society. He is author of Excellence Without a Soul: Does Liberal Education Have a Future? Together, the authors teach Quantitative Reasoning 48, an innovative Harvard course on information for non-technical, non-mathematically oriented students. 00_0137135599_FM.qxd 7/31/08 12:16 PM Page xvii 00_0137135599_FM.qxd 5/7/08 1:00 PM Page xviii CHAPTER 1 Digital Explosion Why Is It Happening, and What Is at Stake? On September 19, 2007, while driving alone near Seattle on her way to work, Tanya Rider went off the road and crashed into a ravine.* For eight days, she was trapped upside down in the wreckage of her car. Severely dehydrated and suffering from injuries to her leg and shoulder, she nearly died of kidney fail- ure. Fortunately, rescuers ultimately found her. She spent months recuperat- ing in a medical facility. Happily, she was able to go home for Christmas. Tanya’s story is not just about a woman, an accident, and a rescue. It is a story about bits—the zeroes and ones that make up all our cell phone conver- sations, bank records, and everything else that gets communicated or stored using modern electronics. Tanya was found because cell phone companies keep records of cell phone locations. When you carry your cell phone, it regularly sends out a digital “ping,” a few bits conveying a “Here I am!” message. Your phone keeps “ping- ing” as long as it remains turned on. Nearby cell phone towers pick up the pings and send them on to your cellular service provider. Your cell phone company uses the pings to direct your incoming calls to the right cell phone towers. Tanya’s cell phone company, Verizon, still had a record of the last location of her cell phone, even after the phone had gone dead. That is how the police found her. So why did it take more than a week? If a woman disappears, her husband can’t just make the police find her by tracing her cell phone records. She has a privacy right, and maybe she has good reason to leave town without telling her husband where she is going. In 1 * Citations of facts and sources appear at the end of the book. A page number and a phrase identify the passage. 01_0137135599_ch01.qxd 4/16/08 1:19 PM Page 1 Tanya’s case, her bank account showed some activity (more bits!) after her disappearance, and the police could not classify her as a “missing person.” In fact, that activity was by her husband. Through some misunderstanding, the police thought he did not have access to the account. Only when the police suspected Tanya’s husband of involvement in her disappearance did they have legal access to the cell phone records. Had they continued to act on the true presumption that he was blameless, Tanya might never have been found. New technologies interacted in an odd way with evolving standards of pri- vacy, telecommunications, and criminal law. The explosive combination almost cost Tanya Rider her life. Her story is dramatic, but every day we encounter unexpected consequences of data flows that could not have hap- pened a few years ago. When you have finished reading this book, you should see the world in a different way. You should hear a story from a friend or on a newscast and say to yourself, “that’s really a bits story,” even if no one mentions anything dig- ital. The movements of physical objects and the actions of flesh and blood human beings are only the surface. To understand what is really going on, you have to see the virtual world, the eerie flow of bits steering the events of life. This book is your guide to this new world. The Explosion of Bits, and Everything Else The world changed very suddenly. Almost everything is stored in a computer somewhere. Court records, grocery purchases, precious family photos, point- less radio programs.... Computers contain a lot of stuff that isn’t useful today but somebody thinks might someday come in handy. It is all being reduced to zeroes and ones—“bits.” The bits are stashed on disks of home computers and in the data centers of big corporations and government agencies. The disks can hold so many bits that there is no need to pick and choose what gets remembered. So much digital information, misinformation, data, and garbage is being squirreled away that most of it will be seen only by computers, never by human eyes. And computers are getting better and better at extracting mean- ing from all those bits—finding patterns that sometimes solve crimes and make useful suggestions, and sometimes reveal things about us we did not expect others to know. The March 2008 resignation of Eliot Spitzer as Governor of New York is a bits story as well as a prostitution story. Under anti-money laundering (AML) rules, banks must report transactions of more than $10,000 to federal regula- tors. None of Spitzer’s alleged payments reached that threshold, but his 2 B L O W N T O B I T S 01_0137135599_ch01.qxd 4/16/08 1:19 PM Page 2