 long run. Airline travel is cheaper than ever before, but few customers are happy with the experience." Given the present state of wireless competition, it's only a matter of time before unlimited calling plans are available nationwide. Wireless number portability (WNP), which began in 2003, likely will be a catalyst for this trend, according to the research firm. 1.4 FOURTH-GENERATION MOBILE SERVICES With the wireless industry looking for new ways of boosting both subscriber numbers and usage, most carriers are already planning fourth-generation (4G) networks. As a result, mobile phone networks are destined to become much faster and more uniform over the next several years. Today's networks, restricted by low bandwidth and a patchwork of incompatible standards, will give way to an interoperable system that supports an array of devices and offers seamless roaming. Imagine a wireless world in which networks provide broadband data and voice, giving users high-quality audio, Internet, and even video services. Users can go anywhere in the world and automatically be handed off to whatever wireless service is available, including cellular, satel- lite, and in-house phone systems. Higher-speed third-generation (3G) mobile services has now rolled out, but 4G technology is waiting in the wings. Upcoming 4G services, intended to provide mobile data at rates of 100 Mbits per second or faster, could begin arriving as soon as 2006. According to the Fourth-Generation Mobile Forum, an international technical body that's focusing on next generation broadband wireless mobile communications, the technology is about to undergo explo- sive growth. In 2000, only eight organizations were involved in 4G research and development. In 2002, over 200 companies and research institutions were conducting 4G projects. By 2008, over $400 billion will be invested in 4G services. Several major carriers have already started 4G testing. Japan's NTT DoCoMo, for example, has been conducting research on 4G mobile commu- nications technology since 199