Bandwidth at the speed of light

As firms struggle for network capacity, a new laser product could be the solution

As firms struggle for network capacity, a new laser product could be the solution

The amount of data moving around corporate networks is increasing faster than the technology can handle.

Where it was once simply a mix of mainframe sessions, limited file transfer and print traffic, the corporate network now encompasses bandwidth hogs such as multimedia, back-up services and Web access from both Internet and intranet sources.

And new applications such as e-commerce, distance learning, computer-based training and information broadcasts have created nightmares for administrators forced to maintain high availability access to data files and key corporate data processes.

The solution has been to upgrade the corporate backbone to Gigabit Ethernet for server-to-server and server-to-hub traffic and speeds of 100mbps for service to the desktop.

This all works fine when an organisation operates from a single building or site that can have inter-building cabling installed without problems. However, if you need to cross public roads or push out an infrastructure across a site where laying fibre is not financially or physically viable, there are limited alternatives available.

Wireless Lan

One alternative is wireless Lan (local area network) technology, which will provide data speeds of up to 10mbps between buildings. Another is short-haul microwave, which provides much higher speeds but brings in to play a number of significant health and safety issues. And a small number of European companies are now making progress with an infrared waveband technology called Laser IR.

The first generation of Laser IR technology suffered from a number of issues, mainly because suppliers were trying to compete with wireless Lans on distance. This meant using high power, extremely expensive components and auto tracking mechanisms that rarely delivered effective long-term communications. The result was that a lot of people dismissed the technology as being of little real commercial value.

However, London-based company Cablefree has now developed a range of second-generation Laser IR products that can provide access speeds from E1 through 10mbps Ethernet up to Gigabit Ethernet for campus and backbone extensions. The products are not only aimed at the corporate extension market but are also being used heavily by telcos and Internet service providers (ISPs) to provide Net access and fibre replacement or extension.

The basic product comes as a pair of solid-state lasers that meet European and UK health and safety regulations for eye safety. This is extremely important because, where a tenant doesn't have access to the roof of their building or the landlord will not allow a fixture to be placed on the roof, the Cablefree system can be mounted behind a window. In such a case, it is important that people such as window cleaners are protected from the beam as well as people in other buildings should the laser somehow be knocked out of alignment.

By using a very narrow beam Cablefree is able to reduce the power required, thus keeping power usage to far less than the average mobile telephone.

This also helps to reduce any issue with environmental interference such as torrential rain, smog or other airborne particles - a hot issue with the current climate change being experienced in the UK.

Global solution

It also means that corporate customers who have offices in areas of the world such as Asia, where monsoons are prevalent, can look to a global solution rather than a mix of technologies in different operating regions.

The degree to which interference can be eliminated has ensured that Cablefree is now winning a lot of the traditional wireless and microwave suppliers' ISPbusiness.

Short haul microwave does not generally suffer from interference because it is a regulated service where frequencies are carefully allocated. Unfortunately, this requires a lot of extensive planning, the building owner's permission over the siting of the dish, frequency allocation from the Government, and, in urban areas, facing up to the increasing difficulty of acquiring a free block of spectrum in which to operate.

Wireless Lan operating in the 2.4GHz Industrial, Scientific and Medical (ISM) band is the most attractive solution as it is unregulated and can be set-up very quickly. However, it does suffer from problems of interference when too many systems are being operated in close proximity. Because this is an unregulated band, interference generally occurs when operators either apply too much power or site their antenna badly.

The use of wireless, especially for ISPs, is on the increase because of the high costs and problems associated with traditional fibre solutions. The number of commercial buildings that are connected to the wider telecommunications backbone via optical fibre is very low with some estimates putting it at, on average, less than 10% in major cities worldwide.

One problem of laying fibre is that the operator needs to obtain permission to dig in the fibre from all the landowners between the exchange and the building. This can be a time consuming and costly business, even when the building is under initial construction.

For existing buildings, this problem is much worse because obtaining permission often means searching through old records. This also applies to buildings that are already wired, and companies are finding they must go through this process even when they are simply looking to add additional capacity.

Additional expense

A further complication is that metropolitan authorities are actively looking to reduce the amount of disruption caused by digging up roads to install new services. There are suggestions of congestion charging for such works and this is likely to add additional cost to already expensive bandwidth.

In the UK, despite moves to ensure that all councils maintain records of all services that have been put into the ground, records are often incomplete and where a provider needs to cross the boundary between one authority and the next, the level of available information is often sparse at best.

It can be seen that all of these areas offer significant opportunities for Laser IR. Firstly, it is an unregulated service so the only issue that needs to be dealt with, from a local authority standpoint, is obtaining the permission to mount the lasers externally.

Interference concerns

Interference concerns are irrelevant with a narrow beam solution and beams can cross over one another without any problem. Systems can also be heavily co-located, allowing service providers to run a high density offering in urban areas.

Bandwidth can be anything from a simple E1 at 2mbps or 10mbps Lan through to 1gbps corporate backbone replacements. The net result is that, where services are required immediately, there is no wait for the fibre and the relevant permissions can be acquired over a period of time.

For the customer and the service provider, there are significant benefits. The Laser IR system is a one-off capital purchase so there are no recurring costs other than bandwidth. And the cost of digging-in the infrastructure is removed from the overall cost of the solution.

With the exception of the entry-level Cablefree Lite product, the system is fully upgradeable and can be managed centrally using SNMP and thus integrate into corporate network management tools. Yet, the most important issue is that the service can be set up in hours, rather than months, ensuring immediate payback for operators and a working system as and when required for the customer.

The advantages of Laser IR mean that it is finding its way into a range of applications. ISPs, such as Soho NET, have started to deploy it in preference to wireless Lan. In the Balkans, the banking industry has deployed high-speed networks using Laser IR. And disaster recovery systems are available from suppliers, such as Aeon Systems, who use Laser IR for transmitting data back to central repositories.

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