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Traffic Engineering Q

Hi ;

I have 2 lines to MPLS cloud as following : CE1--PE1


I want to aggregate the BW on both routers , which is best way to do that , Is it better to terminate both lines on same PE routter or keep them on deferent PE router for redundancy ? and if i keep it on deferents PE's routers Is posible to do 2 TE's for load balance ?



Re: Traffic Engineering Q


what is the underlying issue, which leads to your request?

If you want load balancing from your site to the MPLS cloud, then normal IP routing can be used. We would need some more informations about your topology though (HSRP between CE1 and CE2, or other routers present, how many segments, etc.)

Be aware, that there is no MPLS TE on CE routers, because there is typically no MPLS but only IP (with some exceptions like CsC).

So "aggregating the BW" is an IP task from the CE side and has nothing to do with MPLS.

In an IP solution you can use existing routing protocols (which one?) to distribute traffic onto both links. Load sharing from the MPLS cloud into your site has to be implemented by your SP. You should check with the SP which options exist.

You also could use Multilink PPP between two routers (one PE and one CE), but this removes hardware redundancy.

Regards, Martin

Community Member

Re: Traffic Engineering Q

Thanks Martin , yes in CE side I will use GLBP or MHSRP there is no issue but my concern when we get to MPLS cloud there is 2 PE routers , so if the traffic from both CE routers reach the PE routers and each PE routers get deferent route to destination and one path is faster than the other , then at the destination point it will aggregate the 2 paths with 2 deferent speed, i think this degrade the quality

Re: Traffic Engineering Q


the way you setup load balancing from the CEs to the MPLS cloud prevents this. As one PC will have one CE as default gateway, all the traffic from one PC will go through one path only. Thus no packet reordering will take place and no degradation should be experienced. If a PE has two pathes to a certain destination it depends on the PE load balancing implementation. With Cisco PEs the default behaviour is determined through CEF. Factory default is per destination load balancing. This also means no reordering and attached degradation issues.

Bottom line: unless the SP messes up things there should be no such issues, which you are afraid of.

Hope this helps! Please use the rating system.

Regards, Martin

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