Congestion Resolution: MPLS TE?

[digisnoc1]

I am curious if this is possible to resolve congestion.  

Currently you would have an OSPF network with 1.3 gigs of traffic flowing to a point in the network that has multiple paths. However one of those paths is 1 gig and the other is only 500 mb.  With OSPF i know you could create 2 vlans over 1 path and have the other path and load balance over the 3 but my question is, what if you were to create an MPLS VPN accross the 2 paths/4 routers. Could you possibly use TE to load balance that traffic? Allow ospf to function normally beyond and through the vpn but purly use it to balance the load.

Is the optimal? would there be a better way to do this?

attached is a crude sketch of the idea

[Reza Sharifi]

Assuming the middle section (MPLS-TE) is controlled by your provider, if that is the case you have no control which way the provider will route your traffic. Usually the cost of Gig interface is more than 500Mb circuit.  So you can use the Gig as your primary circuit and the 500Mb as backup.

HTH

[digisnoc1]

This would be a network in my control entirely. what im saying is we have congestion because of the amount of traffic coming in to where i am proposing we put the mpls-te section to address that congestion and have TE load balance for us. Im curious if this is possible or if im not applying the principle correctly.

[Reza Sharifi]

ok, I am not sure how you have 500Mb on one side and Gig on the other side.  If these routers/switches are connected via Ethernet, the speed usually is 100Mb, 1Gig, 10Gig, etc..

If this is the case, the easiest solution would be to upgrade the 500Mb side to Gig and let OSPF load balance the traffic for you.

HTH

[digisnoc1]

This isnt real world. This is purely hypothetical. just trying to ascertain if MPLS-TE can be used in this way.

Also the way that this would happen is via microwave wireless backhauls instead of physical ethernet connections.

[Joseph W. Doherty]

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Posting

Yes, using 3 specific path MPLS tunnels should work similar to using 3 path VLANs.  (Actually, you might only need one extra VLAN or MPLE tunnel, to map out the second path across the 2x bandwidth path.)

Another method would be to use GRE tunnels.  The problem with those, unlike VLANs or MPLS, GRE will shrink max IP MTU (which if you're only using standard Ethernet, but actual path can support larger MTU, e.g. Jumbo Ethernet, that might not be an issue).

A better way might be PfR's PIRO.  The above just balances new flows, but doesn't actually balance path load.  PfR can balance actual path loading.  You also wouldn't need to define 3 paths, either.

[digisnoc1]

ive been looking up PFR and it seems like something that you have to do with BGP and WAN links. The area i need to balance is internal and setting up BGP would not be a viable option there in the network. 

What i have in a GNS3 lab is a tunnel that is pointed over to the other router. The one tunnel is being advertised into ospf. and i can verify that the shortest path with a show ip route does indeed point to the tunnel. and if i show mpls traffic-eng ... it does show that it has two available TE paths. Does this mean that the tunnel will balance onto the available TE paths?

[digisnoc1]

ive been looking up PFR and it seems like something that you have to do with BGP and WAN links. The area i need to balance is internal and setting up BGP would not be a viable option there in the network. 

What i have in a GNS3 lab is a tunnel that is pointed over to the other router. The one tunnel is being advertised into ospf. and i can verify that the shortest path with a show ip route does indeed point to the tunnel. and if i show mpls traffic-eng ... it does show that it has two available TE paths. Does this mean that the tunnel will balance onto the available TE paths?