Wireless Hacks, 2nd Edition

Credits

About the Authors

Rob Flickenger has been a professional systems administrator for more than ten years, and an all-around hacker for as long as he can remember. Rob enjoys spreading the good word of open networks, open standards, and ubiquitous wireless networking. His current professional project is Metrix Communication LLC, which provides wireless hardware and software that embodies the same open source principles he rants about in his books. Rob also works with the U.N. and various international organizations to bring these ideas to places where communications infrastructure is badly needed. He hopes that all of this effort is contributing toward the ultimate goal of infinite bandwidth everywhere for free. He is the author of two other O’Reilly books: Linux Server Hacks and Building Wireless Community Networks, which is now in its second edition.

Roger Weeks has over a decade of experience in systems and network administration. He’s been building Linux systems at home and in the enterprise since 1998, and recommends that you check out http://freenetworks.org if you’re interested in community wireless. He is currently the senior network administrator for Mendocino Community Network, a small ISP in coastal northern California. MCN is owned by the local school district, and puts their profits back into the local schools. Roger is a coauthor of another O’Reilly book, Linux Unwired.

Contributors

The following people contributed their hacks, writing, and inspiration to this book:

• Richard Baguley is a freelance journalist who writes about computers, technology, and video for publications such as PC World, Wired, and camcorderinfo.com. He lives in the San Francisco Bay area with his wife Kath and a French Bulldog called Fester. His home is shared with an ever-changing variety of foster cats who like nothing better than to gnaw on any cables that he leaves lying around, which explains why he likes wireless networking so much.

• Marcel Bilal is a computer scientist, with a focus on Wireless LAN technologies. He lives in Berlin, Germany and works for an IT-service provider (IT-Dienstleistungszentrum Berlin) as a systems admin. You can find him at http://aws.netzfund.de or [e-mail].

• James Duncan Davidson is a freelance author, software developer, and consultant focusing on Mac OS X and related technologies. He is the author of Running Mac OS X Panther, coauthor (with Rael Dornfest) of Mac OS X Panther Hacks, coauthor (with Apple Computer, Inc) of Learning Cocoa with Objective-C, and coauthor (with Michael Beam) of Cocoa in a Nutshell, all published by O’Reilly Media. Duncan is also a contributor to the O’Reilly Network (http://www.oreillynet.com), as well as publisher of his own web site, x180 (http://x180.net/). In what sometimes seems like a previous life, Duncan created the widely used Apache Tomcat and Apache Ant and was instrumental in their donation to the Apache Software Foundation by Sun Microsystems. He was also the specification lead and author of two versions of the Java Servlet API and two versions of the Java API for XML Processing (JAXP).

• Schuyler Erle (http://nocat.net) hacks on free software and agitates for the cause of community networking. Schuyler is also chief architect of NoCatAuth, a leading open source captive portal application.

• Michael Erskine (http://www.freeantennas.com) works at kaballero.com.

• Preston Gralla is the author of more than 30 books about computers and the Internet, including Windows XP Hacks, Internet Annoyances, and Windows XP Power Hound. He’s been writing about technology since the dawn of the PC, was a founding editor of both PC Week and PC/Computing, an executive editor of ZDNet and CNet, and has contributed to dozens of publications, including PC Magazine, The Los Angeles Times, USA Today, and Computerworld, among others.

• Bryan Hurley studies Computer Science at the University of Maryland, Baltimore County. He is working on wearable computing research dealing with location, audio, and mood sensing. In addition to cutting the cord on the PistolMouse, he has built augmented reality systems at the United States Naval Research Laboratory in Washington, D.C. He lives in Columbia, Maryland. Bryan can be contacted at [e-mail].

• Jeff Ishaq (http://www.ishaq.biz) is a software engineer and writer living in Santa Cruz, California. He is the author of Treo Fan Book for O’Reilly, and has been developing Palm software since 1996. In his spare time, he enjoys eating spicy food, trail running, playing guitar, and alpine snowboarding. He hopes someday to organize his office.

• Brian Jepson is an O’Reilly editor, programmer, and coauthor of Mac OS X Tiger for Unix Geeks and Linux Unwired. He’s also a volunteer systems administrator and all-around geek for AS220 (http://www.as220.org), a nonprofit arts center in Providence, Rhode Island. AS220 gives Rhode Island artists uncensored and unjuried forums for their work. These forums include galleries, performance space, and publications. Brian sees to it that technology, especially free software, supports that mission.

• Scott MacHaffie (http://www.nonvi.com/sm) is a programmer. He learned to program in 1980 and has been getting paid for it since 1987. He has a B.S. and an M.S. in Computer Science, from University of Washington and Portland State University, respectively. He has studied Human-Computer Interactions and User Interface design for many years. Scott writes games for Palm OS devices as a hobby. He and his wife are learning to speak Irish Gaelic. Scott also teaches aikido when he can get a break from his twin boys, and he is knowledgeable about early Celtic, Irish, and Scottish history.

• Dr. Trevor Marshall (http://www.trevormarshall.com), based in the heart of Southern California’s “Digital Coast,” offers a full spectrum of consulting services in technologies ranging from Wi-Fi security and Internet infrastructure through RF, hardware, software, and audio/video to biomedical and prepress. Previous speaking engagements have included COMDEX, Microprocessor Forums, and WLAN/Wi-Fi Security conferences in Paris, Boston, and Santa Clara.

• Damon McCormick is a recent University of California, Berkeley, graduate with degrees in Electrical Engineering, Computer Science, and Philosophy. He enjoys the contradiction between an area of study that actively seeks an implementation of strong artificial intelligence and an area of study that claims strong artificial intelligence is practically impossible. Damon admits to computer security research and billiards addictions, and splits his spare time evenly between those activities and working on PlaceSite.

• Yasha Okshtein is an Interdisciplinary Engineering major at The Cooper Union for the Advancement of Science and Art. In his spare time, he tinkers with anything he can get his hands on, including Linux, RC Cars, and various wireless devices. His web site is at http://yasha.okshtein.net and he can be reached at [e-mail].

• Sean Savage is Project PlaceSite’s Founder and Chief Instigator. Sean coined the term zombie effect, which describes feelings of alienation that occur when people in a semipublic place like a cafe or pub tune out the people and activities around them as they focus on laptops, mobile phones, or televisions. The zombie effect, and possibilities for countering it, is a driving force behind Project PlaceSite. Sean also coined the term flash mob, which is now listed in the Oxford English Dictionary and first appeared on his web site (http://cheesebikini.com). In 2005 Sean graduated with a Masters degree from U.C. Berkeley’s School of Information Management & Systems. For two years he studied and designed location-based technology at Berkeley and, during the summer of 2004, at Intel Research Seattle. Sean is also a writer whose work has appeared in Wired, The Washington Post, The Miami Herald, and The Chicago Tribune.

• Terry Schmidt (http://www.nycwireless.net) is a leading expert on wireless networking technologies and applications. He has presented at major information technology conferences, including MacWorld, the O’Reilly Emerging Technologies Conference, and 802.11Planet.

• Cloyce D. Spradling is a full-time sysadmin and full-time developer of benchmarks and benchmark tools for one of SPEC’s (http://www.spec.org) member companies. He likes monkeys, pirates, watching cartoons, and traveling with his wife and their rubber chicken. He can be reached at [e-mail].

• Jo Walsh is a freelance hacker and software artist who started out building web systems for the Guardian, the ICA, and state51 in London. Jo is trying to combine her interests in maps, spatial annotation on the semantic web, Wi-Fi geolocation, public transport planning, open geodata, and bots into something resembling coherence: http://wirelesslondon.info, a localized wireless captive portal service.

• Matt Westervelt is the founder of SeattleWireless (http://seattlewireless.net) and an evangelist for FreeNetworks worldwide. He left the corporate world to start Metrix Communication LLC, a company created to supply FreeNetworkers with high quality, standards-based wireless networking products. As a child, he watched a lot of Sesame Street, and has a firm (perhaps misguided) belief that cooperation can solve a lot of the world’s problems.

• Ron Wickersham (http://www.alembic.com) is an inventor and the Chief Engineer at Alembic, Inc. where he designs guitar electronics. His hobbies involve everything interesting in the Universe including The Amateur Sky Survey and watering the flowers.

• Haihao Wu grew up in Shanghai and lives with his wife in Austin, Texas. He works for Freescale Semiconductor.

• Michael Juntao Yuan (http://www.MichaelYuan.com) is a mobile alpha geek and author of three mobile-technology–related books. Over the last couple of years, he has managed to accumulate more than a dozen smartphones; most of them are Nokia phones. He is the lead developer of Nokia’s Series 40 Java Blueprint Application and is actively involved in various standards committees helping to define the next-generation Java platform on mobile phones. Michael currently works for JBoss Inc., the Professional Open Source software company, focusing on next-generation Java enterprise middleware. Michael has a Ph.D. from the University of Texas at Austin. When he is not working, writing, or playing with gadgets, he likes to travel and take pictures. Check out his picture albums at http://www.jjcafe.net/photography.

Acknowledgments

This book is really a cooperative venture, regardless of the two names on the cover. As Rob said when the second edition was proposed, writing a Hacks book is not only writing, but also project management.

Thanks to all of our contributors who provided such great and new material for the book, and to our editor, Brian Sawyer, who has been a great resource throughout the whole process.

Rob

I’d like to thank my family and friends for their continuing support by giving me the encouragement (and occasionally, solitude) needed to complete my various little projects.

Many hacks in this book were inspired by conversations with countless hackers who willingly share their ideas with anyone who will listen. A few came from the weekly “hack night” sessions that SeattleWireless hosts to foster such cross-pollination of ideas. Without the free and enthusiastic exchange of ideas, this book wouldn’t have been possible. Thank you to all of the brilliant hackers around the planet who know that the value of sharing one’s ideas can greatly exceed the value of keeping an idea to oneself.

Edd Dumbill, Casey Halverson, and Richard Lotz all provided technical review for the book. Ken Caruso and Matt Westervelt provided equipment, ideas, and valuable insight. Thank you, gentlemen!

And thanks everyone at O’Reilly who made this book a reality, and who continue to help relieve information pain in the world.

Roger

I wouldn’t have dived deeply into things wireless if I hadn’t met Rob at one of the early NoCat meetings he held at O’Reilly back in 2001. The next couple of years were full of long-distance network building, late-night hacking, and a real sense of community, not only for me but for everyone who was involved in actually building a community wireless network. I can’t thank Rob enough.

I would also be amiss if I didn’t thank personally all of the “Cats”: Nate Boblitt, Adam Flaherty, Jim Rosenbaum, and Schuyler Erle. There isn’t anything that can’t get fixed, broken, and fixed even better when these guys are in the room.

During the entire time we’ve been married, my wife, Cynthia, has been totally understanding of the life of a geek. She puts up with long technical conversations, motherboards and computer pieces littering the floor, and even the long hours that come with working a network admin job. I love her more than words can express.