At ECOC 2018. as part of the 100G Lambda multisource agreement (MSA) interoperability demonstration, Cisco demonstrated Nexus 32-port 100 GbE & 400 GbE 1RU switches populated with modules from various manufacturers.
In a blog post, Cisco's Mark Nowell writes "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!"
https://blogs.cisco.com/datacenter/cisco-makes-terabit-scale-ethernet-networking-a-reality-with-400-gbe-technology
