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WHY WI-FI WANTS to BE FREE As the Telecommunications Industry Wavers, a Global Grassroots Movement Is Building the Next-Generation Wireless Network

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WHY WI-FI WANTS to BE FREE As the Telecommunications Industry Wavers, a Global Grassroots Movement Is Building the Next-Generation Wireless Network By Terry Schmidt and Anthony Townsend WHY WI-FI WANTS TO BE FREE As the telecommunications industry wavers, a global grassroots movement is building the next-generation wireless network. hile wireless carriers around the world have battled through the telecom bust, a grassroots movement has quietly deployed no-cost open wireless hotspots in cities acrossW the globe. In the process, these activists have trans- formed 802.11b wireless local area network (WLAN) tech- nology from an indoor novelty for cable replacement to an outdoor amenity that transforms the urban landscape—key developments of this grassroots wireless movement are high- lighted here. The community-based open wireless move- ment that has taken root in cities around the world in the last two years has demonstrated an alternative model for the widespread diffusion of wireless broadband networks. The experiences of early efforts in this area offer many insights COMMUNICATIONS OF THE ACM May 2003/Vol. 46, No. 5 47 PUT SIMPLY, WIRELESS NETWORKS WANT TO BE FREE. BY “FREE,” WE MEAN THAT HOMES, OFFICES, AND PUBLIC SPACES WILL INCREASINGLY BE EXPECTED TO PROVIDE HASSLE-FREE WIRELESS BANDWIDTH. into the possible futures for wireless networking. unlimited Wi-Fi access throughout the network. Like the Internet and Web, wireless LANs became In the U.S., wireless hotspots were targeted toward a mass market technology due to open standards that business travelers and were deployed at locations fre- unleashed powerful competitive forces and innova- quented by business travelers, such as airport tion. While many WLAN technologies were being lounges, upscale hotels, and coffee-shop chains. sold throughout the 1990s, it was the establishment However, unlike in Asia, cellular carriers did not of the 802.11b standard by the IEEE, followed by directly own the U.S. hotspot providers. Consumers Apple’s aggressive launch of the Airport line of were slow to subscribe, driven away by average WLAN products in 1999 that set the stage for mass monthly fees of over $50, very limited network cov- market development. After many other market erage, and the proliferation of free Wi-Fi hotspots. entrants, by the summer of 2002 there were an esti- By summer 2002, one of the largest U.S. hotspot mated 15 to 18 million 802.11b networks [3]. companies, MobileStar, was bankrupt. Not surpris- Affectionately renamed “Wi-Fi” (for wireless ingly, the company later re-emerged as a division of fidelity) by a consortium of manufacturers, 802.11b T-Mobile USA, a cellular carrier seeking early entry quickly edged out competing WLAN standards. to the WLAN access market. Even Intel ceded victory, abandoning the competing Hotspot providers (at least in the U.S.) had a HomeRF WLAN standard in early 2001 and throw- challenging road to profitability in a world where ing its weight behind Wi-Fi. By fall 2002, Wi-Fi unmetered Wi-Fi broadband was increasingly plen- emerged as a serious threat to so-called “third-gener- tiful. Driven by the rapid drop in the cost of Wi-Fi ation” cellular data networks, a long anticipated hardware, no-fee wireless networks were popping up upgrade to wide area wireless networks [2]. everywhere—in universities, offices, city parks, and The 802.11b standard was open, which allowed homes. Dartmouth University’s open network in many manufacturers to quickly enter the WLAN New Hampshire alone boasted over 500 nodes cov- market. In 1999, WLAN base stations cost as much ering many of the campus buildings and grounds as $1,000. Competition continually drove prices [3]. By the fall of 2002, there was a good chance that lower, and at the time this article was written the anytime you walked onto a university campus or average price of a Wi-Fi base station was just $100. into a large office building, its owner would be offer- Client devices experienced similar rapid price ing free Wi-Fi connectivity as a basic amenity. declines, dropping to less than $50, and were Thus while pay networks experienced slow sub- quickly integrated as standard equipment in new scriber growth, property owners and building man- laptops and handheld computers. agers moved quickly to provide the valuable amenity of wireless connectivity within their spaces. Like the Building the Hotspots Internet a decade earlier, the idea of a “wireless As the number of Wi-Fi client devices and users cloud” spread from universities into the broader grew during 2000–2002, a massive worldwide ini- market. Once it reached homes and businesses, tak- tiative began to deploy network infrastructure to ing it outdoors was the next step. This would be the support this new broadband medium. New and old province of the free wireless movement. firms were motivated to deploy infrastructure in places where early adopters would congregate. In The Rise of the Open Network South Korea, Japan, and Singapore, wireless carriers As Wi-Fi spread quickly in 2000–2001, activists and raced to deploy Wi-Fi hotspots at popular gathering hackers around the world began testing the limits of places. These Asian hotspot networks leveraged high what could be achieved with this exciting new tech- rates of mobile Internet use with the density of nology. The most novel of the resulting innovations Asian cities to create a successful business model, was the redeployment of Wi-Fi to provide connec- typically charging the equivalent of $15–$20 for tivity not only indoors in homes and offices (the 48 May 2003/Vol. 46, No. 5 COMMUNICATIONS OF THE ACM original design goal), but also outdoors in parks, com). In major cities, the open wireless network now porches, and plazas. These activists quickly found rivals leading commercial WLAN networks. For each other through email and Web connections, and example, at the time this article was written, in New began organizing volunteers and deploying coopera- York City the NYCwireless network (95 active tive public wireless networks. nodes) was competing with the two main pay wire- The hotspots deployed by these grassroots wire- less LAN systems operated by T-Mobile USA (120 less-networking groups were a dramatic departure nodes) and Wayport (3 nodes) [9]. from the pay hotspots set up by companies such as The free wireless movement’s overall sustainability T-Mobile. Instead of requiring expensive usage fees, is being bolstered by expanding participation and these networks would be open to all at absolutely no partnership beyond the core group of individuals cost. Instead of extensive security layers designed to who started it. Spearheaded by NYCwireless’ incor- thwart eavesdropping, users would be expected to poration as a non-profit organization in April 2002, provide the desired level of security themselves using and resulting from collaboration with many existing existing tools like SSH, SSL, PGP, and VPNs. businesses and government agencies, the con- The spread of these free wireless networks was stituency of support behind the idea of ubiquitous, rapid. Most places where you would want wireless free (to the user) wireless networks is rapidly grow- bandwidth already had wired bandwidth in abun- ing. But why do free wireless networks have such dance. Creating a hotspot was just a matter of widespread appeal? installing a wireless base station, or access point, and It is the expert opinion of the authors that the advertising its presence through any of several means popularity of open wireless networks is a combina- provided by the open wireless community.1 For tion of open standards and the benefits of mass-pro- larger areas or outdoor spaces such as parks and duction and interoperability they bring, and the plazas, directional antennas and amplifiers could be intrinsic value that a wireless “cloud” brings to the used to sculpt a coverage zone using the meager one place in which it is located. Compared to the typical watt of power permitted by the FCC for unlicensed cost of waste disposal or powering the lights, band- operators in the 2.4GHz band.2 width is inexpensive. For example, maintaining the Individuals had many incentives to contribute to Bryant Park Wireless Network and leasing its T1 expanding the free network. First, there was a sense backbone connection costs less than the park spends of mutual cooperation: “I will set up my free node in on trash bags!3 Thus it makes more economic sense the hopes that others will too, and I will have access for building owners, schools, and even entire neigh- when I’m away from home.” Second, similar to the borhoods to deploy their own open wireless infra- open source software movement, there was a certain structure, rather than to contract this service out to amount of prestige in the wireless networking com- a for-profit provider. munity for those who were node operators rather Put simply, wireless networks want to be free. By than merely users. Finally, the utopian dream of “free,” we mean that homes, offices, and public completely undermining the stranglehold of cellular spaces will increasingly be expected to provide has- and landline telecommunications companies was an sle-free wireless bandwidth. Open wireless networks, enticing goal. which do not require users to log on or authenticate After two years, the free network movement has their identity, are already widely deployed and offer established beachheads in every major American city, far easier and more uniform access to the Internet and throughout Europe and Australia. This free than any pay network might provide. Usage statistics public hotspot network serves more varied locations support this conclusion as well—the authors’ surveys than any commercial Wi-Fi network. From Manhat- of pay hotspots in Manhattan rarely find active tan’s Bryant Park to Portland’s Pioneer Square, in users, while Bryant Park’s network logs an average of independent coffee shops and on the stoops of over 50 users per weekday.
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