Telstra Global is the latest operator to join a sudden wave of activity on the subsea front, announcing upgrades of multiple Pacific Ocean cables with existing vendor partner Infinera Corp. (Nasdaq: INFN).

The international services unit of the Australian telco giant has deployed Infinera's DTN-X on three routes: The Telstra Endeavour cable that links Sydney and Hawaii; its portion of the Asia America Gateway (AAG) cable that runs between Hawaii and California; and the Reach North Asia Loop (RNAL) cable that lands in Hong Kong, Taiwan, Japan, and South Korea. (See Telstra Taps Infinera for Subsea Upgrades.)

News of these upgrades breaks just a few days after the Australia-Japan Cable (AJC) consortium, which includes Telstra Corp. Ltd. (ASX: TLS; NZK: TLS) and several other carriers, chose Infinera's DTN-X for its own cable upgrade.

It also comes about one year after Telstra Global and Infinera first demonstrated how the soft decision forward error correction (SD-FEC) capabilities of the DTN-X could help maximize available capacity on the operator's portion of the AAG cable. In the year since that demonstration, Telstra Global and many other subsea operators have announced transmission upgrades to 100G. (See Telstra, Infinera Demo Subsea FEC.)

Mark Showalter, senior director of marketing at Infinera, says the reason for all these concurrent upgrades is clear. "I think what we're seeing now, especially between Asia and other regions, is cloud activity putting pressure on cable capacity," he says. "Now that you have FEC and coherent technology available with 100G, a lot of these operators are looking to re-architect their networks -- first terrestrial and now subsea." (See Coherent Breathes New Life Into Subsea.)

Tata Communications Ltd. , NTT Communications Corp. (NYSE: NTT), Southern Cross Cables Ltd. , and several others have been among the subsea cable operators seeking upgrades during the past year, with vendors such as Infinera, Ciena Corp. (NYSE: CIEN), Xtera Communications Inc. (Nasdaq: XCOM) among the beneficiaries. (See Tata Does Subsea 100G With Ciena, Infinera Counts Subsea Wins, NTT Comms Deploys 100G Coherent on PC-1, and Southern Cross Completes 100G Upgrade With Ciena.)

Telstra Global has been working with Infinera since early 2012, when it went shopping for an upgrade to 40G. The DTN-X deployment now sets it up for a future beyond 100G, with the platform's capability to support 500G channels. (See Telstra Deploys Infinera for Subsea Net.)

As the PTC'14 event plays out this week in Hawaii, there could be news of more upgrades and other new projects to come, but just in the past few days we've already seen an announcement of a new cable from Ocean Networks and a new strategic investment for Sea Fibre, in addition to Infinera's upgrade wins. (See Ocean Taps Xtera for Subsea Project and Aquavint Invests in Sea Fibre.)

— Dan O'Shea, Managing Editor, Light Reading