Research consultancy group, amr interactive, has taken an innovative approach to establishing network connectivity between its new premises and office headquarters in Sydney, adopting a free space optics (FSO) solution to transmit information wirelessly.

Faced with the expense of laying fibre cabling in order to connect its new premises to the company's main office, situated around 450 metres away, the company instead decided to invest in a wireless FSO link. Information systems manager, Nathan Tege, said amr interactive looked at a couple of solutions before going with FSO.

"The biggest issue we had with most of them was timing," he said. "The move to new premises came on us very quickly.

"Laying fibre in the street was the first option - mainly because AMR had done that before and management understood the process. I started making the enquiries and was told I wouldn't have the surveys back until after we had moved!

"That's when we knew we had to find something different."

Wireless lights up

FSO is a line-of-sight transmission technology which uses a laser beam between two points to provide optical bandwidth connections for transmitting data, voice and video. FSO devices, which are set up as senders and receivers, are connected to the Internet at each end of the wireless link via optical fibre, and usually fitted to the outside of an organisation's building. FSO links (called bridges) can be set up as point to point or point to multi-point links.

FSO technology, which can provide bandwidth connectivity speeds of up to 2.5Gbps, offers wireless connectivity for locations as far as 4km apart. The technology can transmit information over any protocol.

amr interactive's FSO deployment was undertaken by Simply Wireless, a wireless network solutions provider operating in Sydney and Melbourne.

The FSO bridge consists of a FlightLight 155 Free Space optics bridge based on transmission hardware from FSO specialist company LightPointe. The bridge delivers up to 155Mbps of bandwidth connectivity between amr's two offices.

Simply Wireless CEO, Desmond O'Geran, said the total cost of the FSO solution for amr interactive was in the mid-$40,000s. This included the cost of the hardware (about $30,000), extra fibre cabling, a site survey, deployment, testing and services from Simply Wireless. Simply Wireless also installed an simple network management protocol (SNMP) monitoring module alongside the FSO bridge.

The deployment of the FSO bridge took about half-a-day. The actual configuration of the two FSO transmitters takes 20 to 30 minutes. Although amr did not get final figures on the cost of laying fibre, a rough install figure suggested that fibre would be two-and-a-half times as much, Tegel said.

"But you need to add to that the ongoing rental cost of the cable being in the footpath/pits as well," he said. "This is where it starts to add up." Tegel said the FlightLight laser link would have paid itself off after 12 months.

"If we need to move or change we haven't lost money on a 'hole in the ground'," he said.

Nothing but 'joy'

Tegel said all of the company's servers, with the exception of its financial server, were still located in amr's office headquarters. Staff at the new premises are hooked up to the servers via the FSO link.

"We've been running it for a month so far and it's been nothing but joy," Tegel said. There had been no downtime since the link became live, he said.

As an indication of how much traffic travelled across the link, Tegel said the company generated up to 300MB of data per day. Another benefit of using FSO technology was that it was transparent: users hadn't notice any difference between the traditional fibre link and the new FSO connection, Tegel said.

While amr has decided to opt against wireless voice services and restrict its current use of FSO to data-related services, the company is considering adding mirroring capabilities from the new premises back to the main office into the mix.

This would provide another back-up of data created at the new premises, Tegel said.