Optical transport

Facebook start a new project with "voyager"

http://packetpushers.net/open-optical-facebook-voyager/

Some other information about disagragation of network and the OCP presentation of voyager:
https://code.facebook.com/posts/1887543398133443/disaggregate-networking-recap/

Old way:

What Is 400ZR and Why Is It Important?

Some details about undersea cables

UnderSea Map calbles