FT Telecoms March 2001 / Company Profiles
Atrica - A champion for Optical Ethernet
By Fiona Harvey
Most telecommunications carriers today base their communications networks on the internationally recognised SDH (Synchronous Digital Hierarchy) standard for connecting fibre optic transmission systems.
Most of these networks were originally designed for voice traffic, rather than the data transmissions which are coming to dominate the wires, and for much lower amounts of traffic than are the norm today.
SDH, and the SONET (Synchronous Optical Network) standard, an equivalent of SDH used in the US, have been around since the mid-1980s. The international specification defines a standard rate of transmission at 155.52Mbps (megabits per second).
With the huge increases of data traffic that have accompanied the rise of the internet, carriers are looking to expand the capacity of their networks, and speed up data transmission. To do this, they can either seek to extend and improve upon the SDH specification, or look to newer technologies on which to build their networks.
One such new technology is Optical Ethernet - and one company championing it is the US-based Atrica.
Atrica was born out of 3Com, the big US networking technology company. Spun out into a separate company by a group of 3Com employees last February, Atrica received $4m seed funding from 3Com, and a further $16m of venture capital, mostly from Accel Partners and Benchmark Capital. It now has 100 employees and offices in Silicon Valley, Israel and France.
Optical Ethernet takes the Ethernet standard used in millions of corporate computer networks and adapts it to use at high speeds over larger networks carrying both data and voice traffic. The technology carries the advantage of connecting easily to corporate Local Area Networks, and, proponents claim, will allow faster and more efficient networks. It lets carriers combine Ethernet technology with Dense Wavelength Division Multiplexing, which squeezes greater bandwidth out of fibre by separating transmissions to travel down different light wavelengths on the same fibre.
Atrica envisages the new technology being used in metropolitan area networks, which are typically networks with a radius of between 50km and 100km in sizeable cities, such as Manchester or Frankfurt. "Companies are achieving high speeds on their internal networks, using Gigabit Ethernet technology [permitting speeds of up to 1,000Mbps], and there are plenty of high speed, long distance lines, but the bandwidth bottleneck is in the metropolitan area network. Ethernet is suitable for this because it is interoperable, stable and scalable," says David Yates, vice president of marketing at Atrica.
Optical Ethernet promises speeds of up to 10Gbps, and at lower prices than other technologies: if bandwidth of about 10Gbps today costs about $80,000 on SDH, the price of Optical Ethernet will be about a tenth of that, Atrica claims.
The cost of building new infrastructure for networks is also lowered by using Ethernet: a 155Mbps interface on a SDH multiplexer switch costs between $5,000 and $15,000, but a 100Mbps Ethernet switch port costs less than $500.
Mr Yates predicts that soon almost all traffic will be in the form of Internet Protocol packets, so a network of this type that is optimised for data will be preferable to previous standards attuned to voice. Competing with Atrica, however, are companies that are developing technologies that would optimise SDH for data transmission, such as Alidian and Zaffire in the US.
Carriers might be wary, though, that although data will dominate their networks, voice traffic will still represent an important slice of their business. Ethernet was built for data transmission and has not been able to handle voice. Atrica claims it has been able to integrate voice and data successfully over Optical Ethernet.
Ethernet possesses another advantage over its rival technologies, according to Atrica. It enables to easily guarantee their quality of service. And it lets companies easily reconfigure their networks remotely as their bandwidth needs change.
If carriers do start to investigate the new technology, they are unlikely to make any buying decisions overnight, Mr Yates acknowledges.
"This is one of the biggest capital expenditure decisions a telecoms company has to make. But they need to change the way they think about building their networks. Many carriers will stick with SDH, but many are looking at radical changes," he says.
Atrica's first big trial will be with France Telecom. They will start with laboratory testing over several months and then move on to field tests in two cities in France and Redwood City, California. Other telecoms carriers will be watching carefully to see whether the technology truly lives up to the hype surrounding it. |
