All-optical data centre within reach, claim UCL and Microsoft researchers

Breakthrough research from University College London and Microsoft eliminates major hurdle to all-optical data centre networks

A new technique that synchronises computer clocks in under a billionth of a second could pave the way for “all-optical” networks, potentially leading to dramatically more efficient data centres.

All-optical networks use light photons instead of traditional electronic circuitry to transmit and route data between servers in a data centre.

As, in theory, optical switching enables almost infinite bandwidth while reducing power and cooling requirements, the technology has been touted as a more efficient way for cloud providers to accommodate spiralling server demand.

Until now, hyperscalers have relied on Moore’s Law to accommodate rising demand, but there are concerns this trend is unsustainable due to the difficulty of developing smaller and faster silicon transistors (chips that are already measured in nanometres).

Despite much promise, all-optical networks have been considered impractical compared to traditional networking technology as every optically-connected server has to continually sync its clock time to transmit data — a process which actually reduces overall performance.

However, researchers from University College London and Microsoft have developed a new technique which they claim eliminates the need for continual clock readjustment.

Published this week in Nature Electronics, the researchers’ method involves programming hardware to memorise clock phase values so clock time does not have to be re-checked.

The researchers’ technique reduces clock recovery time to under a nanosecond, thereby boosting optical switching performance — making the technology more powerful than today’s state-of-the-art solutions and practical for modern data centre deployment.

Kari Clark, UCL PhD candidate and lead author of the study said the research makes “optical switching viable for the data centre for the first time,” adding that the technology had the potential to “transform” cloud networking and make technologies like the internet of things and artificial intelligence cheaper, faster and less power-intensive.

“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,” said Dr Hitesh Ballani and Dr Paolo Costa, researchers with Microsoft Research Cambridge and co-authors of the study.

“While there is still a long way to go, this technique brings us a step closer to the vision of an all-optical data centre,” they added.