Fixed mobile convergence: Understanding the landscape

Fixed mobile convergence (FMC), the convergence of wired and wireless technologies into a single solution, is explained in this tip.

Fixed mobile convergence (FMC) is an acronym that is being kicked around by both wireless and wireline vendors. Cellular providers and equipment vendors are all introducing or marketing enterprise mobility products and solutions that offer the ability to virtualise the office and un-tether the worker from the traditional local area network and voice lines.

So what is fixed mobile convergence? FMC is an acronym, not a technology. In essence, the premise behind fixed mobile convergence is the ability to offer voice and data applications via a mobile device. This may seem confusing, as this capability is offered today and FMC is touted as a next-generation capability. Let me explain: Today, you can go to most of the major cellular carriers and purchase cellular phones that offer data capabilities such as email and Web browsing. In most cases, the ability to take calls and respond to emails outside the traditional office environment does represent a virtualisation of the office. When you are in the office, you use your PC and traditional telephone to do your work. When you are out of the office, you use your cell phone to do both voice and data (wireless communication). The traditional office utilises wired connections (PC and phone) or 802.11 Wi-Fi (wireless) connections to communicate (wired communication). These technologies enable mobility, not necessarily fixed mobile convergence.

FMC is the convergence of the wired and the wireless technologies into a single solution. In a true FMC world, you will have one phone that can be used in the office and outside the office. When in the office, the phone communicates over the cellular network to the internal PBX or over an 802.11 WLAN. Outside the office, the phone uses the cellular network as usual. The key factor is the ability to have one phone and one phone number. Convergence almost always results in cost savings and efficiencies because converging the traditional voice network with the cellular voice network reduces the number of devices, maintenance, and the ongoing costs of delivering voice services. In addition, the ability also to deliver data over the converged voice handset allows for tremendous efficiency gains for the mobile workforce.

The landscape for fixed mobile convergence is very confusing because the technology is immature and the number of vendors touting FMC capabilities is expanding. Two basic solutions are being touted as FMC solutions, and they are both being offered by network vendors (not cellular).

One is IP-PBX extension (sometimes called single-mode), and the other is wireless-Wi-Fi convergence (sometimes called dual-mode). In the IP PBX extension track, the IP telephony vendors are offering software that can be loaded onto the phone, which allows the traditional cell phone to communicate directly with the internal enterprise PBX. This is done exclusively over the cellular network. The enterprise must have a gateway that connects to the PBX and the cellular backbone. This allows the cell phone to act and feel like the traditional landline. Now you can have the same number both inside and outside the office, with one voicemail, and you can use traditional PBX capabilities such as 4-digit dial, number look-up and conferencing, as well as a host of other capabilities. Cisco, Avaya, Siemens and RIM are currently offering this solution.

The second option is to use a dual-mode solution. Here, the phone utilises the cellular network when outside the building; when inside, it uses the wireless LAN to communicate with the PBX. The phone must have multiple radios (one for cellular voice, one for wireless 802.11 voice) to make this happen. Cisco, Avaya and Siemens are also playing in this space.

In both of the FMC scenarios described above, the phone is the key. Poor battery life, inconsistent performance, and lack of ruggedness have limited the adoption of fixed mobile convergence solutions. Suffice it to say that FMC is very attractive in terms of capabilities, just not in terms of mature usage. FMC is coming; it just needs more time.

About the author: Robbie Harrell (CCIE#3873) is the National Practice Lead for Advanced Infrastructure Solutions for AT&T. He has more than 10 years of experience providing strategic, business and technical consulting services. Robbie lives in Atlanta and is a graduate of Clemson University. His background includes positions as a principal architect at International Network Services, Lucent, Frontway, Callisma and SBC Communications.

Read more on Voice networking and VoIP