Southern Cross eyes 6 Tbps capacity

Transmission upgrade to provide bigger-than-expected network boost.

Southern Cross Cable has revised upwards the expected capacity gains from a transmission upgrade to its submarine cable network, expecting it to boost the network to "at least" 6 terabits per second (Tbps).

The cable operator had previously thought a maximum 4.8 Tbps was possible under the upgrade to 40 Gbps transmission equipment.

The upgrade was due to take place next year. A vendor selection process was underway.

Southern Cross director of sales and marketing Ross Pfeffer raised the prospect of achieving a total network potential in excess of 6 Tbps.

"When you have things like 40 Gbps [transmission] technology you anticipate it can do this or do that," he said.

"But until [you] actually build it and then test it on live networks [you] don't actually know.

"The most we know about 40 Gbps today on the basis of tests along the segment of our network [is that it] would give us at least 6 Tbps [total network capacity]. We just don't know how much more than that."

A transmission upgrade of this magnitude had not occurred since 2004, when the company moved from 2.5 Gbps to 10 Gbps transmission technology.

The new technology would operate at a rate of 40 Gbps per channel, multiplied by the six fibres used in Southern Cross' 28,500 kilometres of undersea cable linking Australia, New Zealand, the United States, Hawaii and Fiji.

The operator most recently gave the US$1.4 billion network a total protected capacity of up to 1.2 Tbps, up from a previous 240 Gbps.

It also last week trumpeted a successful trial of 100 Gbps transmission technology, which would enable the company to further upgrade the network capacity by 2015.

However, the cable is likely to face stiff competition from a growing number of potential new cable systems linking Australia with the US and South-East Asia.

Those included a newly formed Leighton subsidiary, ASC, which promised 16 Tbps capacity between Perth and Singapore by 2013, as well as New Zealand outfits Kordia and Pacific Fibre offering up to 5.5 Tbps between Sydney and Los Angeles.

Pfeffer said the competition would be unlikely to meet Southern Cross' capacity at time of launch.

"They're all mentioning potential capacities," he said. "Any new [cables] they build will be far less than that - it would be absolute stupidity to go and build an entire cable out to its potential because you would be wasting your money. When you need it you could have it for far less cost."

Telecommunications analysis firm TeleGeography recently estimated an unprecedented US$2.8 billion investment would be spent building 14 new submarine cables globally during 2011.

Trans-Pacific cable systems had increased in capacity by 7 Tbps since 2007 at the time of the report.