FEATURE
THE EVOLVING ROLE OF COHERENT OPTICS IN SUBMARINE NETWORK Connected Data Centers
BY JEAN-MARIE VILAIN AND HICHAM MAALOUF
A
s with all telecom network operators worldwide, undersea cable network operators are striving to scale their networks quickly and efficiently to meet burgeoning demand for bandwidth and to support sophisticated services. One of the key trends in the undersea domain is terrestrial end point connection directly to data centers, circumventing the typical cable station handoff. The impetus for direct data center to data center connection via submarine networks is reduction in equipment requirements and especially in optical-to-electrical-to-optical conversions. Achieving transmission direct to the data center can increase reliability, reduce cost and power consumption, and ensure signal integrity and security. Large private companies are contributing to the data center to data center trend, given that corporations operating global businesses need access to high-capacity, low-latency networks capable of seamlessly connecting their data centers around the globe. Webscale companies like Facebook, Google, and Amazon have been investing in and building undersea cable networks to interconnect their geographically dispersed data centers. An estimated 99 percent of global data traffic flows over subsea networks making network transformation a major focus. With the advent of 5G there is even more pressure on cable network operators to evolve their infrastructure.
PLUGGING IN AT THE DATA CENTER
The end game of global backbone networks connecting directly to terrestrial data centers works well in concept, but success relies on first-time-right execution.
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SUBMARINE TELECOMS MAGAZINE
The gateway to direct data center connectivity is coherent optical technology. Coherent technology is one of the fundamental enablers of network evolution. Throughout the last decade, this technology has paved the way to a lower cost, lower power consumption and smaller from factor line side solution, significantly reducing the investment over legacy line cards. Network operators have attained efficiency gains by reducing the cost per bit and maximizing spectral efficiency by adopting coherent technology. Going forward, coherent technology will remain a key element supporting network transformation. Coherent technology is already widely deployed throughout most network operators’ submarine, backbone, 5G, data center interconnect (DCI), and metro networks. Pluggable coherent transceivers will enable expanding the use of coherent technology in access networks for higher capacity edge connect requirements. How they are used will depend on network topology, traffic capacity, and reach requirements as in submarine networks. Cable network operators are striving to efficiently scale their networks to meet exponential bandwidth growth and support evolving services. Data center operators are also scaling up to meet bandwidth demands and cope with the massive amount of interconnection among data centers today. Latest advancements in pluggable optics have increased automation and reduced cost to create a flexible, programmable hardware layer. Coherent pluggables can help support the higher speeds and capabilities delivered on subsea networks, with increased reliability.