Cogent Layer 2

Thu Oct 15 06:01:03 UTC 2020

On Wed, Oct 14, 2020, at 20:38, Rod Beck wrote:
> You are correct that if you have 
> to carve it up into a lots of VLANs, it would be a nightmare. But 
> Hibernia was a true wholesale carrier providing backbone to clients, 
> not links distributing traffic to lots of user end points. 

The fact that there was a "switched Ethernet" commercial service doesn't mean that the underlying transport was really "switched ethernet" end-to-end. Ethernet over MPLS is a VERY old concept (VLL, VPWS, VPLS, lately EVPN), and these days Ethernet over VXLAN is becoming more and more popular (mostly EVPN).

A carrier using a pure, unencapsulated, end-to-end ethernet for transport over 1000s of km is (and was for at least 15 years) a disaster waiting to happen. Almost all ethernet services (switched, not switched or otherwise) use some form of encapsulation (IP or MPLS, see above) these days.