The IEEE came to a consensus to develop 400 Gigabit Ethernet technology in 2012. In those six years since, the demand for bandwidth has never slowed due to use cases such as cloud networking. Cisco has been tracking this rapid uptick in storage and networking bandwidth through the Cisco Global Cloud Index for several years now, which predicts that the world will exceed the 14 zettabyte mark for global cloud IP traffic by 2020.

Since 2012 there has also been a whole industry effort behind the necessary technology advances to support 400 Gb/s Ethernet including new IEEE standards, new high bandwidth switching silicon, a new pluggable QSFP-DD form factor, and new high speed signalling technology (PAM4) for both electrical and optical interfaces.

This week sees the first public demonstration of many of these building blocks all coming together at the European Conference on Optical Communication (ECOC). The 100G Lambda multisource agreement (MSA) is running an interoperability demonstration of both 100 GbE and 400 GbE optics all based on 100 Gb/s per wavelength optical technology. The optical modules from a number of optical module vendors are available in QSFP28 and QSFP-DD form factors. Central to the demonstration, the Cisco Nexus 32-port 100 GbE & 400 GbE 1RU switches populated with various modules plugged in and interoperating with traffic flowing.

The Cisco Nexus switch has already been put to the test in the Ethernet Alliance's High-Speed Ethernet Plugfest in August. The plugfest enabled members to test their equipment in private against other members equipment in order to shake out any issues. Cisco was the only networking vendor to participate with a 400 GbE product successfully testing against test equipment, optical modules and copper cables - confirming it is ready to go!

It is very exciting that 400 GbE is now becoming available for testing, deployment, and adoption by network operators, paving the way for Terabit Scale Ethernet being a mainstream technology. There will be many more announcements in the future but it is important to mark this key milestone!