Carrier Ethernet: An Interim Step in Mobile Backhaul Evolution

How many vendor whitepapers have you read in the last several years about mobile backhaul evolution? You know the story. TDM backhaul gives way to Carrier Ethernet to meet increasing capacity requirements and to deliver lower cost per megabyte. The whitepapers exalt the virtues of Carrier Ethernet in building hierarchical backhaul networks for all-IP RAN in 3G/4G networks.

That the ideal solution for all-IP RAN is a Layer 2 network is a puzzling conclusion. As the intelligence moves toward the network edge, IP is  a natural fit.

  • IP networks provides better scalability properties, particularly in building a hierarchical backhaul network
  • IP networks offer improved load balancing and predictive failover
  • IP has a richer QoS feature set
  • IP networks are easier to troubleshoot than complex Layer 2 networks
  • Multicast

I predict that the mobile  providers that purchase Carrier Ethernet service will push their backhaul providers to offer an IP service over the next several years. Ideally, the IP service would be offered  in the form of a Layer 3 VPN. Even a vanilla IP service would be better than Carrier Ethernet. In this scenario, mobile providers could roll their own VPN with technologies such as L2TPv3. The backhaul providers that purchase IPv4/IPv6-ready gear will have a step up on the competition.