Web Giants Push For Optical Advances
Representatives from Facebook and other data center titans used the recent Open Compute Summit (San Jose, California) to push for significant shifts in networking, storage and software product development since advances are urgently needed by operators who are struggling to keep their heads above the crashing tidal wave of data that flows more deeply and quickly with each passing month.
In a move that may foreshadow adjustments in photonic integrated circuit (PIC) product development road maps, Facebook said that it will need 400G switch ASICs with optical interfaces within three years to make ready for the company’s next large-scale network upgrade. To demonstrate its present state of affairs, Facebook invited one of its lead engineers to describe how rack-scale switches were lashed together with cables in 2017 when network demands were about to overwhelm existing system capabilities.
“We were already using the largest switches available and there was nothing else we could readily buy…to fill the need," said a Facebook project manager.
To solve the dilemma, Facebook engineers stacked dozens of its Wedge 100 switches in a rack, with connections made with cabling and patch panels. Facebook said the project, borne from necessity, eventually resulted in what was called the Fabric Aggregator, a 100 T/bps switch that went from concept to production in five months.
To make the next leap to 400G interfaces—which the company hopes to do in about two years, Facebook is calling for work to bring optical interfaces directly to switch ASICs. This is a considerably larger leap than some in industry had set their sights on achieving. Facebook engineers said a key operational concern is cooling separate ASICs and optical modules, fueling speculation that this presents opportunities for PIC innovators working on disruptive approaches that will substantially reduce cooling requirements compared to existing technologies.