With an increasingly mobile workforce, the need for roaming staff to stay connected to the internet, email and other office systems from wherever they happen to be is more important than ever.

Inmarsat's regional BGAN system is a portable satellite modem that provides ubiquitous connectivity from virtually any location with a clear view of the sky, but low bandwidth and slow connections demand a degree of patience when using it.

Cost is also an issue, with the BGAN modem reviewed here priced at around £1,000 + VAT, and service provider bandwidth charges are as high as £10 to £15 per megabyte transmitted.

The ruggedised modem is roughly the size of a standard A4 format notebook PC, but a couple of inches thicker and a lot lighter. Alongside the two rubber power-on and mode-select buttons on the front, there is a row of LEDs that indicate whether the device is being used on battery or mains power, and whether the link to the host PC is using Bluetooth, Ethernet or USB connectivity.

The requisite SIM card is about the same size as those used in mobile phones, and inhabits a small pull-out compartment on one side, next to the removable battery.

Once the drivers and connection software are installed from the single CD, the program brings up an internet connection wizard that runs the user through configuration. In our lab tests, the software eventually recognised the USB cable and automatically opened the pointing screen that helps to position the modem for optimum signal strength.

Siting is crucial to getting an initial network connection - the device must be placed on a flat surface with a clear view of the sky before connection to Inmarsat's geostationary satellites is assured. The sign on the side "Caution: RF Radiation Keep Away One Metre" gives a little cause for concern, although the USB, Ethernet and power cables supplied are conveniently long to help put the modem in a safe position relative to the user.

The software indicates the precise direction that the device's hinged lid should be pointed, as well as the correct angle, using beeps to direct the user to the best configuration. We tested the modem at various locations within the UK and found that it always needed to be pointed to the south east and it needed an angle between 17 to 18 degrees to get the best signal.

We were able to get a connection from behind window panes, but the satellite signal was always stronger when the modem was placed outdoors. The strength of the signal can fluctuate, meaning users might have a connection at one moment, and nothing the next, which sometimes prevented us from getting a connection at all, or broke off the one we had achieved.

Although we were unable to measure bandwidth precisely, the experience when browsing the web is very similar to using a dial-up modem, indicating approximately 42kbit/s downstream in most instances.

Satellite systems have long been called the Hobson's Choice of fixed data connections, a last resort that saves the day when there is no other type of access technology available. Considering this performance it is not difficult to see why.

The regional BGAN is better suited to truly mobile users who work outside in very remote areas where broadband options are non-existent, GSM and GPRS coverage is patchy or unavailable, and even dial-up analogue lines are hard to find.

Price: £1,000 + VAT

Contact: Inmarsat 020 7728 1000