While we acknowledge this as pure fiction, the dream of unfettered communication is becoming more of a requirement in today's business world. Being mobile is more the norm than ever before. Use of mobile handsets to meet enterprise mobility requirements seems to be a partial answer, but only addresses one part of the overall requirements: off-campus connectivity. However, there's no seamless connectivity with the corporate information systems and often there's limited cellular coverage inside office or public buildings.

The advent of enterprise-wide Wi-Fi adoption has brought about the possibility of delivering a technology that bridges wireless carrier connectivity with on-campus WLAN connectivity—Fixed/mobile convergence (FMC). This term was coined by early mobility advocates of providing seamless bridging between Wi-Fi and cellular networks. These technologies, now in pilot testing, extend cellular connectivity to places where cellular coverage is weak or non-existent. Being able to begin a phone call in the wireless network and continue that call when traversing network boundaries will provide true mobility. Such evolving technologies bring the hope of mobility to users, but are not always adequate in addressing the full range of mobility requirements.

FMC alternatives FMC solutions, in principle, all propose supplying voice and data services based on seamless integration of cellular and wireless packet-switch technologies/services. All of the announced FMC solutions fall into one of two general categories, hosted either by fixed, wireless, or hybrid carriers (carrier-centric), or by enterprises (enterprise-centric). The major difference between these two approaches is where the application control point resides, and results in functionally distinct solutions. Carrier-centric solutions view Wi-Fi networks as a potential transport mechanism for traffic roaming between fixed and cellular networks, with application control remaining with the carrier/service-provider network

(Fig. 1). At its design core, an enterprise-centric solution presumes that the Wi-Fi and wired-network services are a single logical resource under the control of the enterprise, with application control being retained within the enterprise. Such a design allows for a more "native" architecture to be implemented where voice-over-IP (VoIP) can be supported as part of a solution complementing the mobility capabilities of the WAN component.