REVIEW - FreeBird flies in to improve laser communications

The growth of Lans and Wans means that buildings in a campus-type environment often need to be connected. Universities and local authorities are especially aware of the problems this can present.

The process is expensive. Roads may have to be dug up, cable bought and laid, and if there are any problems you can forget about your Christmas bonus. An alternative approach is to implement a wireless connection.

Many vendors offer microwave campus links, but few dabble in the intricate world of lasers.

However, the Freespace Turbo, developed by FreeBird Communications and available in the UK through Black Box, will offer protocol-independent laser connectivity between buildings up to 300m apart.

Big things come in small packages

The whole package arrived in our Labs in a number of cardboard boxes.

This was disappointing: lasers should be small and intricate devices shouldn't they?

Thankfully, most of the space was taken up by the monolithic mounting brackets

designed to maintain the all-important line-of-sight, in every conceivable weather condition.

The notoriety of the British weather means any data sent through air has to accommodate huge margins of error. One minute we can be experiencing a heat-wave, and the next it starts snowing. Because of this, Black Box quotes the slightly smaller distance of 300m (greater distances can be achieved in good conditions) to allow for a worst case scenario. The product also comes with a lens defroster to combat our island's freezing winters.

The laser devices are approximately the size of the CCTV cameras you will find busily recording Saturday night activities in town centres up and down the country. James Bond territory they aren't, but the boxes are certainly functional. As well as the lasers, we were provided with two remote control boxes which contained the circuitry and power.

We connected the lasers via the fibre cable to a 10/100Mbps Ethernet switch at either end, and then patched these to a couple of servers.

The first thing we had to sort out was line-of-sight. Each laser device emits an oval-shaped beam of light, which is transmitted to the other at a 90 degree angle. Black Box claims this increases the catchment area and improves reliability.

Getting it all in the line of fire

Physically lining up the lasers was easy with the help of the integrated telescopes, which increased the level of accuracy.

We could then finely adjust them using a loopback procedure. By creating a loop at one end of the link, we were able to use the supplied phone to check for signal strength; the higher the pitch, the better the signal. A signal-strength meter on the back of the laser devices also helps to verify this, with readings of one (poor) to nine (excellent).

Although this is an easy, and straightforward procedure, Black Box will arrange for third-party installation companies to set up the laser link.

After all, clambering about on the roof of a building may not be everyone's idea of fun.

Once the product was installed and set up we could try out the link.

Pinging either end provided us with the evidence that the link was functioning properly.

Because the laser link is transparent and protocol-independent, it will support speeds of up to 155Mbps. However, we linked up using the more popular 100Mbps Ethernet, which worked without a hitch.

Dealing with the safety aspects

As soon as lasers are mentioned most people's reaction is to question the safety of such devices. The sci-fi vision of high-powered lasers cutting through sheet metal and concrete is very powerful.

There are three power settings: low, medium and high. The low power level, we are assured by Black Box, is no stronger than the emission from a TV remote control unit. The high power setting was not much more impressive

For those Star Wars fans out there who envisaged laser fights across the Wan, this may be slightly disappointing.

Despite this, the manual goes into some depth on the subject of safety. Some of the words of wisdom include: do not look directly into the laser beam; and do not drill holes in the power box!

Assuming you do neither of these, the Freespace Turbo would be a valuable addition to any campus network. Black Box claims the system is ideal if installing fibre or a leased line is uneconomical. It can also be used in mobile networks such as those at conferences or shows, temporary connections or installations where traditional methods would be too costly or impractical.

Make it easy on yourself

Overall, the sheer simplicity of a product, which we imagined would be far more complicated, makes the Freespace an attractive proposition.

Assuming we are not thrown back to the days of pea-soup fog, then your data could be flying through the air between buildings at speeds of up to 155Mbps before you can say "fibre-optic installation".

LOWDOWN ON THE LASER

The Freespace Turbo uses a Class IIIb laser, which operates at a wavelength of 780nm. The signal is invisible to the naked eye; and has a low output power of less than 20mW.

Eye damage can occur if you stare closely at the laser for a long time.

The system's manual goes into detail about safe distances from which you can view a transmitting laser. With the naked eye, you can view it on full power from 37ft. Using the telescope this increases to 107ft, although you should try to avoid eye contact.

The product has received CE Mark and EN 60 950 certification.

PRODUCT INFO

FREEBIRD FREESPACE TURBO £12,000

What does it do? Provides protocol-independent laser links between buildings up to 300m apart

- Simple to install and use; protocol-independent; beats digging up roads!

- Fine-tuning of line-of-sight could be more scientific; no support for Gigabit Ethernet.

Availability: Black Box (0118) 9655100

www.blackbox.co.uk.