Optical Connections Magazine Autumn 2023

ANTONY SAVVAS SUBSEA CABLES

Laying out the underwater optical opportunities OPPORTUNITIES AND OBSTACLES:

There is plenty of activity around subsea/submarine optical cables. As well as the telcos/communications service providers, both US big tech and the hyperscale cloud service providers are getting in on the act. So what’s driving the demand, where is the activity, and what tech is being used to get more data over these long subsea routes? Antony Savvas looks at the reasons for this and some of the obstacles in front of it.

DEMAND Analyst house Dell’Oro Group’s five- year forecast for the optical transport equipment market indicates the activity in the subsea sector, saying the value of the overall market will be worth US$83 billion by 2027. This is 10% higher than its previous rolling five-year forecast. The majority of this revenue will come from sales of coherent DWDM systems, it says. “We slightly raised our outlook for optical transport equipment,” says Jimmy Yu, vice president at Dell’Oro Group. “We believe the demand for long haul equipment is better than we had originally thought. Although year-to- year spending on optical equipment is lumpy, the direction for bandwidth consumption remains steady, pointing up and to the right.” Geoff Bennett, director of solutions and technology at Infinera, says, “According to Telegeography, annual growth of international capacity is around 35%, with most of the demand driven by two content providers,

increasing demand for more capacity and faster speeds, but also because some of the older cables are beginning to degrade,” says Sumimoto. TECHNOLOGY The technology driving high-capacity submarine cables focuses on two areas. One is the evolution of the submarine cable technology (known as the “wet plant”) and the other is the development of optical transmitters/ receivers (the “transponders”) that are deployed at the ends of the cable. Wet plant has passed through several generations that include dispersion-managed cables, uncompensated cables, and space division multiplexing (SDM) cables. The first generation of SDM is in service today. Dispersion-managed and uncompensated cables are designed to maximise capacity per fibre pair, and SDM optimises the capacity per cable, through economising on electrical power consumption per fibre

Google and Meta/Facebook.” As Meta generates most of its money through advertising, it knows exactly how much money it loses if a user scrolls on a Facebook page without seeing an ad. That makes it highly motivated to deliver very fast response times. “They do this by copying information between their hyperscale data centres all around the world to keep the information as ‘local’ as possible. And submarine network capacity is required to interconnect these data centres,” says Bennett. NTT concurs on the need for low latency. “With increasing demand for cloud solutions and lower latency, the undersea internet cable sector is quickly becoming more critical to global internet infrastructure, especially after the pandemic,” says Takahiro Sumimoto, senior vice president of the marine cable division at NTT. NTT sees a “capacity shortage everywhere”. “We urgently need to construct new cables both to fill the

34

| ISSUE 34 | Q3 2023

www.opticalconnectionsnews.com

Made with FlippingBook - Share PDF online