Analysts estimate that cellular services now represent about 25% of the telecom budget, and that percentage is growing steadily with the increased use of mobile services coupled with the byzantine pricing plans offered by the cellular carriers. As a large percentage of that cellular usage occurs while the user is in the office, migrating that traffic to a wireless LAN is an obvious alternative. At VoiceCon San Francisco last month, I heard an interesting testimonial for the cost effectiveness of WLAN voice and fixed-mobile convergence.Despite developments in WLAN technology, it is no secret that WLAN voice has been slow to catch on. Current deployments are typically limited to a few defined verticals like healthcare and retail. In those environments, we are equipping lower-level workers (e.g. nurses and retail clerks) with mobile handsets that operate exclusively over the WLAN infrastructure. While that strategy does provide a cost effective mobile capability for users whose mobility is limited to the building or campus, it does not address the requirements of managerial and professional workers who divide their time between the office and off site tasks.
At VoiceCon San Francisco, I got to host a panel titled User Case Studies: Mobility in the Enterprise. One of the participants, Greg Ireland, Executive Office at the Thirteenth District Court in New Mexico had a great story to tell about his implementation of a fixed-mobile convergence solution from DiVitas Networks.
According to Mr. Ireland, the Court had some powerful incentives to pursue WLAN voice for both technical and business reasons. To begin with, the design of their buildings resulted in poor indoor cellular coverage. That difficulty proved particularly problematic for one segment of their users who had to be accessible continuously. As it turns out, the Court's staff attorneys split their time among four courthouses as well as several other facilities. Along with their other duties, the staff attorneys run free legal clinics for people who wish to represent themselves before the court.
The staff attorneys routinely provide their phone numbers to people who attend their clinics so they can field follow-up questions. While this is certainly a useful program for the public, the other payoff is that it helps the court run more efficiently. People appearing before a judge need to know what will be expected of them and what documentation they will have to provide. If the litigants come unprepared, matters are delayed, wasting expensive court time, and their appearances often must be rescheduled. Providing continuous access to those staff attorneys with a single number and a single voice mailbox helps the wheels of justice turn more smoothly.
For the deployment, the attorneys were equipped with dual mode Nokia E71 handsets that can operate over both T-Mobile's GSM cellular service and the court's Trapeze Networks WLAN infrastructure. The solution provides single number access, and if the user is within range of the WLAN, the call is delivered over it. If the user is not reachable over the WLAN, the call is delivered via T-Mobile's cellular network. The DiVitas system also supports transparent handoffs between the WLAN and cellular environments, so a user can start a call on the WLAN and it will transition to the cellular network if they move out of range.
The icing on the cake is that the configuration not only helps the Court provide better service and function more efficiently, it also saves money. As much of the calling has been shifted from the cellular network to the WLAN, Mr. Ireland has been able to scale back his cellular plan, cutting the cellular bill for those users by 60%. They are now looking to extend it to probation officers who have similar work patterns and communication requirements.
Mr. Ireland modestly downplays his networking expertise, but he has certainly gotten the essential ideas right. His is still a relatively small-scale deployment, but it does demonstrate that FMC is workable, and the results are certainly worth the effort. With cellular costs spiraling out of control and network managers under increasing pressure to deliver savings, it may be that 2009 is the year that fixed mobile convergence finally takes off.
