Offering fixed mobile convergence (FMC) services can help wireless LAN solution providers add considerable value by helping customers reduce total cost of operation, improve reliability and increase business productivity.
Customers will use wireless to support many business applications. But, according to the latest Webtorials State of the WLAN survey, the single most important 802.11n application is "adding VoIP to Wi-Fi data loads." Furthermore, almost three out of four companies surveyed already use or plan to use dual-mode 802.11/cellular smartphones. Together, these trends are laying the foundation for fixed mobile convergence. As a wireless LAN solution provider, you are well positioned to help your customers take advantage of fixed mobile convergence technologies.
Fixed mobile convergence capitalizes on existing investment in fixed network assets to augment cellular voice services. By integrating the services offered by otherwise-independent cellular networks and corporate wired and/or wireless LANs, FMC lets users make and receive calls through a single converged mobile handset and number. Potential business benefits of FMC range from better indoor coverage and efficiency to lower equipment and service costs.
Fundamental challenges of offering fixed mobile convergence services
FMC's premise may be simple, but the devil is in the details. Enterprises often think of FMC as a chance to bypass expensive carrier toll charges -- for example, letting mobile workers conduct lengthy overseas calls over inter-office VoIP trunks instead of racking up huge cellular roaming fees. But inside designated areas (e.g., your carrier's national footprint), mobile-to-mobile cellular calls are often free. FMC must thus understand cellular service contracts to make intelligent call routing decisions.
Furthermore, cost is not always top-dog: When a user roams into a cellular or WLAN "black hole," FMC must do whatever it takes to complete seamless handoff and avoid call disruption. Finally, while most PBXs can easily forward incoming calls to a mobile worker's cell phone, employers may also want to control outgoing call routing so all business communication originates from a single (published office) number.
These examples illustrate FMC's fundamental challenge: getting two independent networks to play well together, even when doing so will not benefit both network owners. Not surprisingly, carrier-based FMC solutions are relatively few and far between. Nonetheless, WLAN solution providers should familiarize themselves with any FMC solutions offered by carriers in their region. For example, providers in the U.S. might want to learn about T-Mobile's Wi-Fi Calling for Business and how T-Mobile customers can route cellular calls over their enterprise WLAN. However, most providers will probably want to focus their own FMC-related efforts on carrier-neutral solutions.
Rolling out enterprise fixed mobile convergence
Enterprise-based FMC extends a corporate network to deliver a consistent set of services to converged voice handsets that roam between private WLANs and public networks. Unlike carrier-based approaches, enterprise-based solutions require no FMC-specific collaboration with carriers. Instead, cellular IP data services are treated like residential broadband WLANs and public Wi-Fi hotspots -- FMC simply chooses the best available "pipe" to connect each mobile handset's calls through the enterprise's IP PBX.
To roll out enterprise FMC, customers must already have an enterprise VoIP network, composed of IP PBXs, telephony servers and inter-office VoIP trunks. WLAN solution providers can assist with VoIP network deployment by selling and supporting the 802.11 infrastructure needed to connect the PBX to on-premise VoIP handsets.
Some business needs can be met using single-mode 802.11-only handsets -- for example, warehouse staff and retail clerks who spend all day on their feet but never leave the building. Other workers (e.g., sales, service, delivery) already carry cell phones -- to use FMC, they must transition to dual-mode 802.11/cellular handsets. In either case, solution providers may earn additional revenue by getting involved in mobile VoIP handset procurement and provisioning.
Furthermore, each handset model has its own 802.11 capabilities; vendor specifications like minimum recommended signal strength vary greatly. FMC deployments may thus require (re)engineering and/or upgrading of WLAN infrastructure to satisfy VoIP coverage, latency and jitter requirements. Customers may need help mapping wireless-to-wired quality of service and defining ideal VoIP handset configurations. They may also expect their WLAN solution providers to use voice quality metrics like R-Value and MOS to diagnose problems like "sticky" clients and overloaded APs.
How FMC helps wireless LAN solution providers move up the food chain
Wireless LAN solution providers that want to "move up the food chain" may wish to sell, install and support enterprise FMC customer premises equipment (CPE). Although enterprise FMC platforms vary widely, there are two common approaches: extend the enterprise PBX or install a purpose-built mobility controller.
Many PBXs can support FMC services, either by adding feature groups to the PBX itself or by interfacing the PBX with an adjunct server. Here, the PBX is responsible for routing business calls -- incoming and outgoing -- to mobile phones over internal or external IP networks. Common PBX calling features like corporate directory look-up and 4-digit dialing can be provided to converged VoIP handsets, no matter how those handsets are connected. Many of these platforms can also provide unified communications services such as integrated messaging and telepresence. However, they generally must be paired with PBX-specific VoIP handsets or softphone programs. Providers that want to pursue resale and support opportunities in this arena should look at offerings from vendors like Avaya, Cisco, Microsoft, NEC and Siemens.
Providers that prefer not to specialize in one or more PBX systems can pursue a different kind of enterprise FMC: a third-party mobility appliance that interfaces with mobility client software installed on ordinary dual-mode cell phones. Here, the appliance tracks each phone's location and makes policy-based routing decisions to be carried out by the client (for example, triggering an 802.11-connected phone to switch a call to 3G when leaving the office). This turns ordinary cell phones (e.g., Windows Mobile, BlackBerry, Symbian, iPhone) into FMC handsets that deliver productivity enhancements like one-number reachability, unified messaging, and telepresence without being tied to one kind of PBX. WLAN solution providers looking to enter this emerging market may want to partner with mobility appliance vendors like Agito, DiVitas, Tango and Varaha.
Read the previous tip in this series by Lisa Phifer, "Upgrading customers to 802.11n wireless networks."
Lisa Phifer is president of Core Competence Inc., a consulting firm specializing in network security and management technology. For nearly 20 years, she has been involved in the design, implementation and evaluation of data communications, internetworking, security and network management products.
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