I'm having a real difficult time understanding MPLS TE? Does anyone have a link or technotes that explains TE?
Thanks in advance.
Another option is to look at Dynamips which allows you to emulate 7200 routers and this would then allow you to lab up MPLS-TE.
thanks I thought to focus on conceptual difference with normal IP routing.
the tunnel is a logical interface defined only on originator node.
the tunnel is unidirectional (this is different from GRE tunnels) and works only in outbound direction.
the destination of tunnel 1 can be the originator of tunnel 2 with destination = originator of tunnel 1
see this document
you need on physical interfaces:
mpls traffic-eng tunnels
ip rsvp bandwidth value1 value2
also on the routing protocol you need to enable MPLS TE extensions, to define the MPLS TE router-id;
Having OSPF is a good starting point because only OSPF and IS-IS support MPLS TE.
Hope to help
to keep it simple
MPLS TE can create pre-established paths like FR PVCs or ATM PVCs over IPv4/MPLS networks.
This creates a big difference with normal IP routing:
in normal IP routing the packet is examined and routed at each router next-hop.
if I want to divert some traffic on an alternate path that spans on three routers with IP routing I need:
a PBR rule at each router hop to enforce the packets on the intended path otherwise traffic is sent along lowest cost path.
With MPLS TE a pipe is created and device at the beginning on the pipe places traffic into it.
devices in the middle don't need any config change (no PBR on intermediate devices)they just switch the external MPLS labels
this can be done because in configuring the MPLS TE tunnel I can provide a so called explicit path that lists the devices the tunnel should go through.
each MPLS TE router can be:
an originator of tunnels
a final destination of tunnels
a device in the middle of other tunnels
Hope to help
What exactly are you struggling with.
At a very high-level MPLS-TE allows you control which path traffic takes so you can send higher priority traffic over one path and less important traffic over another.
It also allows you reserve resources within the MPLS network so that if you want to send traffic over a certain path but that path must meet certain conditions in terms of performance, you can ensure that those conditions are met before sending the traffic.