One of the UK's top wireless analysts has warned businesses to consider carefully any deployment of converged fixed-line and mobile solutions.
Fixed-mobile convergence allows phone calls to be routed over a choice of radio technologies with just one handset for each user. Many vendors and service providers are widely publicising such offerings, arguing they will cut corporate IT costs.
But Lars Vestergaard, research director for wireless communications at global analyst company IDC, told a conference of IT professionals on Wednesday, "I'm really concerned about how useful that is for you. Be hesitant with convergence. Make sure they [suppliers] only sell it to you when it's ready."
Vestergaard took issue in particular with BT's Fusion service, which routes mobile calls over a firm's wireless LAN and out onto the public telephone network via the company's own telephone exchange, or PBX. The analyst said there were plenty of other ways to route calls out through the PBX without having to use Wi-Fi networks. "I would suggest that you wait for a couple of years for complex [fixed-mobile] installations," Vestergaard said. "There are some clever things you can do with a PBX. It doesn't even have to be IP or hybrid. You can do many of these things with a normal PBX."
One of the reasons behind Vestergaard's argument is a standard called SIP (Session Initiation Protocol). Although SIP is still immature in its development, it should in the future provide a much cleaner and efficient handoff between different radio technologies.
BT uses another standard, UMA (Unlicensed Mobile Access), in the Fusion service. Vestergaard said, "Is UMA the future? If SIP progresses as it is looking, then UMA may be useless in two years."
Telecoms operators are investigating a range of alternative approaches to fixed-mobile convergence. Colt, Cable&Wireless and O2 are all planning to build GSM networks indoors, of which the first two will carry calls out through the PBX. And the likes of Nokia and Ericsson are developing carrier infrastructure, which allow users to use their mobile phone as a corporate extension.
Orange is pursuing fixed-mobile convergence in the same manner as BT, but the mobile phone operator has yet to provide services to UK businesses.