e specification for an efficient packet-based air interface optimized for the transport of IP-based services. The goal is to enable global deployment of low- cost, ubiquitous, interoperable, and always-on multivendor mobile broadband wireless access networks. IEEE 802.20 has designed a new physical layer (Layer 1 protocol) and MAC/link layer (Layer 2 protocol) around IP packet Layer 3. It can operate in licensed bands below 3.5GHz, with cell ranges of 9 miles (15 km) or more. IEEE 802.20 can operate at speeds of up to 155 mph (250 kph). While the data rate and range of Mobile-Fi are only half those of Mobile WiMax, Mobile-Fi is inherently more mobile. It has an astonishing latency of just 10 milliseconds (500 milliseconds is standard for 3G communications) and can maintain integrity at speeds as high as 155 mph (250 kph), compared to just 60 mph (100 kph) for WiMax. Because it uses more common spectrum-licensed bands up to 3.5GHz-it also offers global mobility, handoff, and roaming support. Chapter 15 WMANs, WLANs, and WPANs Whereas Mobile WiMax is looking at the mobile user walking around with a PDA or laptop, Mobile-Fi addresses high-speed mobility issues. One key difference is the manner in which the two standards are deployed. One assumption is that the carriers are going to deploy Mobile WiMax in their existing (802.16a) footprint as opposed to deploying a more widespread footprint, like a cellular network. Because Mobile-Fi is aimed at more ubiquitous coverage, a larger footprint will be required. Countries and companies often seek to control the market by developing stan- dards they hope will dominate the global scene. The United States has led the way with IEEE standards, and the European Union's ETSI standards are their counter- parts. The work of standards consensus is ongoing, uncertain, and difficult to pre- dict. Mobile operators, who are generally friendly to Mobile WiMax, see Mobile-Fi as a competing standard that could make their 3G licenses worth rather less than they paid for them. The fact that