Siemens Communications has launched an appliance that bridges voice communications between corporate wireless LANs and the cellphone network.

The HiPath MobileConnect system uses an appliance, similar to the one launched by DiVitas last week, which lets enterprise users on dual-mode handsets use corporate VOIP and data services over both Wi-Fi and cellular networks.

The product uses a SIP connection to a corporate PBX, and client software running on one of two dual-mode handsets, the Nokia E60 and the Fujutsu-Siemens Pocket LOOX..

Unlike DiVitas's product, Siemens' won't let users dial from a public hotspot in its first release. Siemens, whch makes PBXs, also doesn't include a PBX alternative, unlike DiVitas, wihch includes the open source Asterix IP PBX.

This product class, often referred to as fixed-mobile convergence, is still in its infancy, but large numbers of network vendors are involved, promising to boost productivity and extend enterprise management and security to smartphones loaded with sensitive corporate data.

The Siemens HiPath Mobile Connect Appliance continuously monitors the mobile users handset, via the companion client application loaded on a dual-mode phone. The appliance keeps a SIP registry of all client handsets, such as dual-mode phones or Wi-Fi VOIP handsets, and it tracks the presence of the handsets. A built-in SIP server links the appliance with a SIP-based PBX. The PBX maintains its function as the clearinghouse for all incoming and outgoing enterprise calls.

The arrangement lets users have one phone number, one voicemail, and access to a range of PBX features, says Luc Roy, vice president, product marketing, Siemens Communications. Outside users, such as customers or employees on the road, can place a cellular call to you at the enterprise, and the HiPath software will bridge this call to the corporate WLAN and use the Wi-Fi connection to ring your dual-mode phone.

The appliance can also switch you from a Wi-Fi connection, as you exit the building into a parking lot for example, to your cellular carrier's net. The client software detects when the Wi-Fi signal is weakening, as you walk out of range. Then the appliance calls your cellular number through the PBX, conferences the Wi-Fi and cellular voice sessions, and then drops the Wi-Fi call.

Calls made or taken over either wireless nets, as long as they go through the corporate PBX, are able to make use of PBX features such as voicemail, call forwarding, and so on.

Chris Silva, an analyst at Forrester Research, said the Siemens MobileConnect product will do well in industries like health care and manufacturing. "When you look at the advantage to health care, the benefit of reaching a surgeon across cellular and Wi-Fi networks is pretty clear, but the benefit to a salesperson is a little fuzzy," Silva said.

The appliance will be available in April, in 3 models, supporting 10, 20, or 150 users. The US price for the appliance ranges from US$3,950 to $39,500; the license costs range between about $2,600 for 10 users to about $18,000 for 150.

Wi-Fi technology in Siemens HiPath range is provided by Chantry Networks, which Siemens acquired in 2004. While some had feared that Chantry's technology would be swallowed up and lost in the inward-looking process of integrating with Siemens' systems, this launch - which we predicted last year, appears to be evidence of a continuing vision.