Soliton solution for longest overland, repeaterless link

Soliton technology is proving itself in Australia's rugged outback, and now Marconi believes the principle is likely to be bound for Europe

By Marc Mabon Marconi

Long-haul carrier, Amcom IP1, Australia, is employing Marconi's ultra-long haul soliton-based technology as part of its Amcom IP1 project to develop a high-speed transcontinental optical-fibre link. The DWDM (dense wave division multiplexing) backbone link will stretch 3,875 km between Perth and Melbourne via Adelaide.

Marconi's soliton-based UPLx160 equipment is to be deployed for the 2,840km Adelaide-Perth leg of Amcom IP1, initially with eight wavelengths - all of them already committed to customers. When completed it will be the world's longest commercial deployment of an overland optical transmission network without regeneration.

The soliton technology revolutionises the economics of transmitting data over vast distances as it requires less electronics than traditional long haul networks because the signal does not need to be continually regenerated along the network. Instead, terminal equipment is only needed at each end of the network making for lower maintenance and operational costs. It is therefore an ideal solution for large land masses such as Australia, the United States, China and pan-Europe.

Amcom IP1 managing director Andy Mclean said, "Upgrading to the UPLx160 is allowing us the flexibility to add wavelengths for our customers as needed and take advantage of the cost benefits provided by the soliton technology.

"There has been no impact to our existing timeframes and we are on track to meet our aim to provide one of the most efficient long haul networks in Australia."

UPLx160 also provides the scalability to add more wavelengths, and hence bandwidth capacity, as further equipment only needs to be installed at the network endpoints rather than at each regeneration point.

This means less electronics and lower labour costs for each change. The network management system (NMS) automatically re-adjusts when wavelengths are added or removed. UPLx160 provides up to 160 wavelengths at 10Gbit/s up to a 3,000 km range.

Technological advances combined with the growth in voice and data traffic - fuelled by the Internet - presented Marconi with an opportunity to develop high-speed, unregenerated ULH transmissions. The system utilising "dispersion managed solitons" also provides intermediate add-drop capability allowing carriers to add and drop any number of channels at any site along the route.

Upturn for soliton technology
Analysts predict that the market for ULH technology will see increasing deployment of soliton-based technology over the next five years. David Krozier, senior analyst at US-based research company RHK Inc. suggests that in the long term carriers will see operational cost savings from ELH/ULH systems because visits to intermediate huts in remote areas will be minimal as adding or dropping channels can be achieved at the terminal locations. His comments were made in last year's RHK report Long-haul Transport & Optical Networks, North America: Market Forecast for long-haul WDM.

Krozier also argues that the elimination of regenerators and the deployment of optical switch systems will open the door for dynamic optical networks where bandwidth connections are established instantly as needed and where needed. Carriers have told RHK that a DWDM system reach of 1,500 km will eliminate the need for 80% of regenerators deployed today.

"From talking with a number of vendors, I expect new DWDM technology will reduce the cost of deployment per Gbit/second/km by a factor of two to three times in the next 12 to 24 months," says Krozier.

With costs savings of some magnitude, it is likely that the industry will see more and more deployments using the same technologies implemented in the Amcom IP1 project. Marconi is aiming to achieve far longer distances with the same amplifier span, or enable longer spans over the original distance. In effect, we will be adding more flexibility and increased robustness, upgrading the unregenerated distance capability in future releases to distances of 5,000km.

Europe next for ULH networks
The experience of Amcom in Australia and emerging trends suggest that ULH networks with optical channel add-drop capabilities, could persuade European operators to adopt ULH systems to serve the length and breadth of Europe with branches to the disparate commercial centres scattered across the continent.

RHK's Krozier adds, "High capacity ELH/ULH systems will have value in European networks even though intercity distances are shorter on average than in North America, for example.

"This is because the reach capability of ELH/ULH systems will span long routes while optical add-drop multiplexers (OADM) will provide bandwidth connectivity to intermediate locations along the route. This approach will be more cost effective than regenerating all transiting traffic at every intermediate city."

For Amcom, the development of the Perth-to-Melbourne network is part of an ambitious growth strategy designed to establish the company as a leading national broadband infrastructure carrier.

The strategy includes:

Developing backbone fibre-optic networks in some of Australia's regional cities and financial centres by negotiating in-building access to central business district office blocks and offering customers broadband capacity via "last-mile" connectivity;
Providing national door-to-door fibre service by building new inter-city links or leasing existing infrastructure capacity; and
Developing a national network by establishing PoPs (Points of Presence) in Melbourne, Sydney and Brisbane through alliances with established carriers.

"In corporate boardrooms and government offices in Western Australia," said Andy McLean, CEO of fibre-optic-based carrier Amcom Telecommunications, "the word broadband is suddenly on everybody's lips. Amcom now has the capacity to deliver a full range of business services.

"That means voice, data, fax and high-speed Internet access, as well as such bandwidth-hungry applications as video-streaming, off-site back-up services, interactive video conferencing, data bureau access, e-commerce, Internet telephony and virtual private networks," he says.

First stage acceptance testing for the Amcom IP1 equipment was completed last month and now 54% of the cable between Melbourne and Perth has been laid, with the Melbourne to Adelaide leg expected to be fully operational this month, and the whole network from Perth to Melbourne to be up and running by December 2002. Amcom IP1 is already signing up wholesale customers to a network stretching from Perth to Brisbane.

Amcom's inner-city Perth, Adelaide and Darwin broadband networks also employ Marconi's switching systems to power high-speed traffic across a fibre-optic synchronous digital hierarchy (SDH) transmission backbone. SMA Series 3 synchronous add-drop multiplexers have been deployed to support efficient traffic delivery. The company is also looking at deploying Marconi's ASX-1200 multiservice switch for its resilience, scalability, fast restoration and flexibility of service.

As Amcom IP1 continues its developments across a number of fronts, the Australian business and government customer should benefit. The company is evolving a cost-effective, flexible and scalable national broadband infrastructure that will allow it to establish competitive advantage by developing differentiating services, by passing operational savings on to customers, and by allowing rapid responses to changes in traffic patterns and customer networking needs.

Amcom is currently in the process of developing a novel "boutique-bandwidth" concept, built around a customer-accessed web portal that will allow customers to select what bandwidth capacity they want and when they want it. They will even be able to choose a specific daytime bandwidth capacity for point-to-point data links and then, at night, move to a different capacity to handle data back-up needs.

Marc Mabon
Marconi Plc
Email [email protected]

Marc Mabon is VP & General Manager, Ultra-Long Haul division, Marconi plc