Recently, the industry has been pondering whether the next big leap for Ethernet should be 400Gbps or 1Tbps.

The conversation probably feels a little familiar. In the last go-round, the industry split between advocates for 40Gbps and those for 100Gbps. In the end, the IEEE worked on standards for both speeds of Ethernet in parallel, at the same time. Those standards are expected to ratify next year.

At the Ethernet Alliance’s recent pow-wow on the next steps for Ethernet technology, Chris Cole of Finisar advocated using 16 links running at 25Gbps each to get to 400Gbps. Some others have indicated that 20Gbps links would be the way to go.

At the same event, Facebook stood up and said they’d like to see an effort get under way toward terabit-speed Ethernet, because the company is seeing some pressure in certain parts of its data centers, where the links are too constricting. Plus, the company is seeing such phenomenal growth in its traffic that if it extrapolates, it can see terabit Ethernet becoming a necessity.

I touched on terabit Ethernet a year and a half ago, when people were talking it up. At the time, the year 2015 was being thrown around as a possible timeframe for standardizing on the high-speed networking technology. But getting to a terabit per second may prove to be more difficult than getting to 400Gbps, and so we may see two separate efforts this time around, instead of the parallel work we saw in 40Gbps and 100Gbps.