FEATURE
The Need for Intelligent Optical Power Management BY GEOFF BENNETT
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MAKING OPEN SUBMARINE CABLES WORK
here are over 550 submarine cables under the seas and oceans of the planet – 480 in operation and a further 70 under construction. Over 99% of intercontinental traffic passes over these cables (not via satellites), and they carry updates from our Facebook friends, our Google searches, and over $10 trillion in financial transactions every day. These cables are typically designed with a 25-year engineering life. Think about that for a moment…a cable that is 20 years old today may have at least another five years of operational life in it. But since it was designed, the potential capacity of such a cable has increased by a factor of 12 or more thanks to the evolution of coherent transponder technologies.
32 SUBMARINE TELECOMS FORUM MAGAZINE
These mid-life upgrades are vital to maintaining the economic effectiveness of the cable – but who provides those updated transponders? You can see from Figure 1 that, over the past 25 years or so, submarine cable technology has also evolved, with different generations being focused on different types of transponder, and different capacity growth strategies. In the early days of submarine cable projects, it was normal for the entire project to be carried out by a single company – including the wet plant (everything that’s under the water), the power feed equipment (PFE), and the submarine line terminal equipment (SLTE – the terminal unit, transponders, and optical power management). Today we refer to these as “turnkey” projects, and they are much less