CCDE – MPLS-TE Auto Tunnels
This post will briefly discuss the challenges of manually setting up MPLS-TE tunnels and how Auto Tunnels can lessen the burden of MPLS-TE tunnels.
One of the main challenges with traffic engineering and MPLS-TE is the number of tunnels that will be needed. To setup tunnels between all PE’s may not be a scalable solution. For a provider with 200 PE’s, 199 tunnels would have to be configured on each PE and that is if only one traffic class is used. This would mean that 39800 tunnels would be present in the network. If you then want to add a tunnel for voice at each PE you end up with 398 tunnels per PE and a total of 79600 tunnels.
Another option is to enable tunnels only on the P routers. If the number of P routers are 20, then each P router would need 19 tunnels and we would have 380 tunnels in total or 760 if adding an extra tunnel for voice. This is a much more reasonable number. It would require to enable LDP over the tunnels if MPLS L3VPNs are in use to have an end to end LSP. With the P to P tunnels we Continue reading