Convergence is bandied about in the world of technology. Think of convergence as a techie's Swiss Army knife. We have cellular telephones that can play video games and MP3s players that can take pictures. Who knows what else they will be able to do in the coming years. Cisco is no stranger to the world of convergence. In the realm of wireless networks, one of the more compelling and useful devices is the Cisco Wireless 7920 IP phone. This telephone, shown in Figure 1-20, looks like a cellular telephone; however, it connects via the WLAN infrastructure (through an Aironet AP, for instance) then to the organization's gateway to allow VoIP telephone calls.
Figure 1-20. Cisco Wireless 7920 IP Phone
The phone uses the 802.11b protocol and Cisco CallManager. The product is ideally suited for environments in which users need telephony, but are constantly on the move and cannot be pinned down to a hardwired telephone. For example, hospitals, warehouses, universities, and retailers are ideally suited for these telephones.
The 7920 IP phone works with a VoIP-enabled network with an AP, but it will not work with cellular telephone networks. If you get outside the range of the organization's APs, the phone does not work. Look for this to be enhanced in the future as Cisco works with cellular companies to make a product that works in both environments.