While many companies still see office wireless LANs as a new thing, Inmarsat is onto its second generation, having first moved to WLAN in 1999. The company, which runs a global satellite network for companies running ships and aeroplanes, has changed its working practices thanks to WLAN, but the upgrade has involved a major change in technology.

Staff that won't stand still
"For most people, wireless has replaced wired," says Peter Smith, IT manager at Inmarsat. "The wired network is still there if people want it."

In the company's offices in City Road, London, staff move from place to place, so Inmarsat needed a network that could respond to that. "Inmarsat is an engineering company," he explains. "Projects are set up and work from one office; they could last for a week or six years. We wanted a solution that was inherently flexible."

In 1999, the company started replacing desktop systems with laptops and put in a wireless LAN system, based on Lucent's access points. This was before the Wi-Fi standards were complete but users picked it up enthusiastically. In meetings, action items are completed before people go back to their offices and get distracted, and users can set up workgroups wherever makes most sense. "Office moves and conferences have given us a return on investment," says Smith. "It maximises our use of the building and minimises the costs of moves."

The company now has 250 people on that network, many of whom roam between the office WLAN and their own wireless network at home. Mostly the applications they use are straightforward: Outlook email, the Web and software development, says Smith.

Time for a change
Predictably enough, Inmarsat eventually suffered the fate of the leading edge user. By the time everyone else was jumping onto the bandwagon, it was outgrowing its first system.

For various reasons, the first system was creaking by 2003.

  • It had pre-standard cryptography, and didn't meet the Wi-Fi specifications, so it did not properly support Centrino.
  • It suffered from interference with other 802.11b networks: there are now fourteen of them in neighbouring buildings, says Smith.
  • It was heavy on administration

  • The bandwidth could not be increased.
  • The system had reached the maximum number of base stations it could support

Looking for a way to replace or extend its system, Inmarsat was approached by a service provider suggesting that it might like to create a public/private hotspot, sharing the costs and revenue, but the provider could not come up with a satisfactory deal.

Having had four years of satisfactory service from its Lucent kit, Inmarsat approached the current incarnation of the company. The original Lucent WLAN equipment has evolved and is now owned by Proxim, but that company did not have a strong enough switch and management story for Smith: "There were technical problems," he says.

The best approach in the end was to upgrade to a three-band 802.11a/b/g wireless LAN system, with Aruba the chosen supplier (see our review of Aruba). "Upgrading to tri-band was more complicated than a virgin installation," says Smith, although the promise of new features such as load-balancing and self-healing should lead to lower costs in the long run.

The company is running both networks side by side, with the Aruba system only operating on 802.11a's 5GHz band, until it is steady enough to shut off the Lucent kit and open up 802.11b/g on the Aruba.

No Voice on Wi-Fi
Data mobility in the office would have been pointless without voice mobility. A group of users moving to a different office for a new project would have been pointless if all their phone calls still went to their old desk phone.

So Inmarsat decided to have voice mobility - but went for DECT and not voice on WLAN, a decision which makes sense given the problems with voice on Wi-Fi.

Using DECT means that users have to carry two phones, since the industry is still looking for the holy grail that will combine the office phone extension with the cellphone. Smith cheerfully says that's not much of a problem. In the office, Inmarsat people simply turn off the mobile phone and have calls redirected to their office number, so calls to their mobile reach their DECT phone.

And no public hotspot use - or not much
"People could use public Wi-Fi, but tend not to," says Smith, airing his secpticism of another fashionable wireless idea. Inmarsat people don't tend to take laptops when travelling. They carry BlackBerries for email. "You can't justify a £1000 laptop for doing email," he says.

Since those devices can pick up email almost anywhere, and the company has a very good competitive deal for GPRS data public Wi-Fi is rarely needed.