-fashioned landlines). Unfortunately, in the realm of data, there are no set standards for data compres- sion; many techniques exist, and overall, data compression is underused. This page intentionally left blank Chapter Wireless WANs It is abundantly clear that wireless networks are a very important part of our future, promising to dramatically change the way society and industry function. Wireless networks fall into the same domains as wireline networks-wide area net- works (WANs), metropolitan area networks (MANs), local area networks (LANs), and personal area networks (PANs)-and are applied in support of a growing num- ber of applications, including mobile (such as cellular and PCS systems), fixed (as in wireless local loop), broadcast (television), and sensor-based (such as RFID) networks. This chapter explores wireless wide area network (WWAN) standards and sys- items. WANs can be global, national, or regional in scope. Traditional WWAN solu- tions include cellular radio and PCS networks (including analog and digital cellular) as well as early wireless data networks (i.e., Cellular Digital Packet Data [CDPD] and packet radio). Newer generations are focused on supporting high- speed data as well as video and multimedia, with increased emphasis on mobile content delivery. Given the basic human desire and need for freedom of movement, it is little sur- prise that the demand for wireless network solutions is enormous. With the intro- duction of cellular communications, we saw an increasing demand for wireless services. The growth was so rapid that by 2002, we witnessed a major shift in net- work usage: For the first time in the history of telecommunications, the number of mobile subscribers exceeded the number of fixed lines. And that trend continues. According to the ITU, at year-end 2004, the total number of mobile subscribers was Chapter 14 Wireless WANs 1.75 billion, while the total number of fixed lines worldwide was 1.2 billion. By Sep- tember 2005, the number of mobile subscriber connections exceeded 2 b