US comms developer Smith Micro has claimed at Mobile World Congress that it can provide persistent secure sessions between mobile devices and enterprise applications, even when the client device moves from one type of connection to another.

The company said this means a user could connect via the office LAN or WLAN, then move outside and switch to wireless broadband or a public hotspot, say, without having to log into the VPN or the application again.

The technology relies upon a VPN gateway device which communicates with a VPN mobility client and a connection manager on the device. The client software includes an auto-disconnect security feature - this senses a wired LAN connection and disables the wireless connections to prevent the device from becoming an ad-hoc hotspot.

Smith Micro said that the client software supports some 300 different connection devices, such as Wi-Fi adapters and 3G modems, and 200 carriers world-wide. It also allows the IT manager to push applications to the mobile device, customise device properties and enforce policies.

So far the client software is only available for Windows PCs and Windows Mobile or PocketPC hand-helds.

However, Smith Micro has also just made its first steps into Symbian elsewhere in its product line-up, with the release of a fixed-mobile convergence (FMC) client for Series 60 and UIQ. The software, called QuickLink IMS, allows WiFi-enabled phones to roam seamlessly between WiFi and cellular.