If you have been wondering, how do the online activities take place!? There are data centers behind every online activity, i.e., at the back of everything we do, such as storing files, uploading photos, creating webpages, or rendering online services. However, due to the server traffic increase by approximately 70%, it becomes hard to meet the need for the existing technologies. The optical network makes use of light to transmit data and that represents a promising alternative. But, it has limited viability as the server has to continuously adjust the clock time according to the incoming data, which leads to lower overall performance.

In the study published in Nature Electronics, it shows that by synchronizing clocks of all connected servers via optical fiber, and by programming hardware to memorize the clock phase value so that it doesn’t have to be re-checked, the time to “recover” the clock can be eliminated.

PhD candidate Kari Clark (Optical Networks Group, UCL Electronic and amp; Electrical Engineering, winner of the EPSRC Connected Nation Pioneers competition), the lead author of the study, said: “Our research makes optical switching viable for the data center for the first time by providing a solution to the clock synchronization problem. It has the potential to transform communication between computers in the cloud, making key future technologies like the internet of things and artificial intelligence cheaper, faster and consume less power.”

Until now, the dependency was on Moore’s law of networking that supported electronic switch integrated circuits doubling their data transmission at the same power and cost. The efficiency and sustainability of this process are now increasingly questioned when the silicon transistors have to be made smaller and faster.

Dr. Hitesh Ballani and Dr. Paolo Costa, researchers with Microsoft Research Cambridge and co-authors of the study, added: “With the expected slowdown of Moore’s Law and ever-increasing cloud traffic, all-optical networks represent an attractive technology that has remained elusive so far. We are very excited by this collaboration with the UCL Optical Networks Group, which started from Kari’s internship in our lab back in 2016 and evolved into a multi-year journey as part of the Optics for the Cloud Research Alliance. While there is still a long way to go, this technique brings us a step closer to the vision of an all-optical data center.”

Dr. Zhixin Liu (Optical Networks Group, UCL Electronic and amp; Electrical Engineering), the senior author of the study, said: “We started this work by investigating how to support future cloud services beyond the end of Moore’s law. By bringing the top minds from cloud operators and optical communication research, we propose a future-proof alternative using optics, helping data centers to cope with demand in the long term.”

Demonstration by the authors laid down that reducing the clock recovery time to less than a nanosecond increased the performance of optical switching compared to state-of-the-art solutions. Such an action will make it practical for data centers and unlock the full potential.