Fresh connectivity woes appear to have struck a segment of the aging SEA-ME-WE 3 submarine cable which leads to Australia. A repair job last month to fix damage that occurred in September was not satisfactorily completed, according to The Register.

Australian Internet service provider iiNet had advised customers over the weekend to expect an increase in latency when browsing international sites due to “a submarine cable fault impacting our international links between Perth and Singapore.” The notice promised an update in a week’s time, suggesting that it is not an issue that can be quickly rectified.

subsea cable
– Nexans

Trouble at sea

It’s not the first time that SEA-ME-WE 3 has run into problems. We reported late last year on how a cable fault in the section between Singapore and Indonesia caused similar slow Internet access for iiNet users.

At 39,000km, SEA-ME-WE 3 is the longest telecoms cable in the world, spanning from from Germany to Australia and Japan, with some 39 landing stations in between. 

The name stands for South East Asia - Middle East - Western Europe, and the cable system itself has two fiber pairs, carrying 48 wavelengths of 10 Gbps or 480 Gbps in each direction.

sea me we 3 route by jp lon.
SEA-ME-WE 3 route – J P Lon / Wikipedia

Perth lifeline

Importantly, SEA-ME-WE 3 is the sole cable serving Perth from overseas at the moment. There are alternative network paths through Sydney to Hong Kong, but these introduces significant delays, increasing latency due to the circuitous route.

Errant ship anchor in shallower water and earthquakes are what typically causes damage to undersea cables. The segment of SEA-ME-WE 3 leading to Australia takes a route through Indonesia, which is a region known to experience hundreds of earthquake every year.

For now, the Submarine Cable Map service provided by TeleGeography pointed to several submarine cables currently under construction to link up the Singapore to Perth route. However, the earliest estimated availability for service date is in late 2016, so it’s at least another year before the reliance on SEA-ME-WE 3 can be alleviated.

subsea fiber cable construction
Subsea fiber cable construction – OOna Raisanen / Wikipedia