ransport of voice or video or data over such a fast layer 2 network arrangement. Of course, ATM itself was supposed to run over an appropriately supportive layer 1 such as SONET/SDH, ²7 but this is beyond the scope of our discussion. There are ample references for the interested reader to pursue the subject. In the evolution of the newly convergent networks, the concept of optical networking starts appear- ing often, and ATM does not seem to be part of the new backbone technology landscape that is tak- ing shape for the longer run. Some industry insiders already envision the demise and elimination altogether of the ATM layer (for instance, running under IP and over SONET/SDH, which would run over optical wavelength division multiplexing [WDM]) in the effort to ultimately have IP run directly over the newer technologies of optical WDM. 28 One of the reasons for such a bleak outlook ATM's inefficient transmission layer. This problem includes ATM Adaptation Layer level 5 (AAL5) and cell overhead, which when combined approaches 30 percent. As a result, it overrides the advantages of multiservice integration and QoS functionality that ATM purports to offer. ²9 WIRELESS NETWORKS AND MOBILITY In the 1980s, the first analog cellular networks appeared timidly in the United States and Europe. They were an instant success with business people and the public at large. As the PC liberated the tormented corporate user from the need to be attached to the mainframe when he or she had some data-related work (IT) to accomplish, the arrival of the mobile telephone liberated users from the telephone jack on the wall. It enabled users to roam around while doing their business and leading their lives more productively and efficiently. Europeans embraced the wireless technologies much faster and to a larger extent than Americans SO they moved quickly to the second generation of wireless networking-the digital Global System for Mobile communication (GSM) standard (helped by an intergovernment- guided standardization process). The United