The Challenge of Wi-Fi Roaming

W i-Fi—consisting of the IEEE 802-11a, 802.11b, and 802.11g technologies—has proven to be a fast wireless-networking approach that is relatively easy and inexpensive to implement. The technology is particularly popular in North America and Asia. About 21 million Wi-Fi (short for wireless fidelity) cards will ship worldwide this year, and 33 million will ship in 2004, said Gemma Paulo, senior analyst with In-Stat/MDR, a market research firm. About two-thirds of these cards will be used in business settings. However, business networking no longer happens just in offices. It occurs in coffee shops, airports, hotels, and convention centers. Thus, as Wi-Fi equipped laptops and PDAs become commonplace, the demand for public Wi-Fi access points—also called hotspots—will grow. Ken Dulaney, a vice president for mobile computing and research director for Gartner Inc., a market analysis firm, predicts “100,000 hotspots within the next five years.” Today, there are somewhat more than 10,000. In the process, as Figure 1 shows, Gartner predicts continuing increased global sales of public hotspot accesspoint equipment. According to Art Tyde, chief operating officer of Sputnik, a Wi-Fi software company, the technology is already becoming “like a utility.” In every new technology park or business hotel, he said, people are beginning to expect Wi-Fi. However, the technology faces a critical challenge to its continued popularity and success: Seamless roaming between different networks is difficult for various technical and business reasons. Roaming is difficult in part because the technologies used in different systems don’t always work together. Also, service providers’ billing and authentication systems sometimes aren’t compatible. Security is another concern. Service providers also must figure out business models for Wi-Fi roaming, including ways to divide up user payments to make sure all participating carriers get paid. Finally, carriers want to figure out ways that Wi-Fi users can roam from their networks to cellular networks. This would, for example, let users begin working at an airport on a laptop via a Wi-Fi hotspot and then continue via a cellular network until they get to their office and can switch to a traditional LAN. To solve these problems, companies are working on a variety of approaches to extend Wi-Fi’s capabilities, appeal, and potential for generating income. Industry observers say more people would use the technology more often if they could roam among networks, working with one carrier in numerous locations. Carriers would also support Wi-Fi roaming because it would extend the reach of their service and attract more customers.