CCDE – Carrier Supporting Carrier
Introduction
In the previous post I showed some of the options two interconnect two AS so that a customer can buy a VPN in two different locations from two different SPs. There is another technology called Carrier Supporting Carrier or Carrier of Carriers. This technology is used when a customer buys a circuit from an SP, Internet service or L3 VPN and that SP uses another SP to carry their traffic between the locations. The SP connecting the customer is then the customer carrier and the SP providing the backbone is the backbone carrier. It is also possible to combine CSC with the Inter-AS options in the previous post, I will show an example of this being used in a real life network in the research world.
Carrier Supporting Carrier
CSC is a technology used to expand the reach of a SP by using another SP as transport. The concept is shown in the following diagram.

The customer carrier is providing a service to the customer. It can be an Internet service, MPLS switched or not or an MPLS L3 VPN. The CSC VPN service provides MPLS transport for the customer carrier. It is also sometimes referred to as Continue reading



I’ve had an interesting few months doing WAN circuit turn-ups for a new Data Centre. I dealt with three major carriers, and each experience was worse than the next. I’m not sure why I held such high expectations but I was surprised by their hopeless inefficiency in delivering what should have been a standard product. In this post I’ll examine the problems I saw and their root causes.