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New Member

Multilink PPP on T1's/T3's

Hi folks, before I begin I want to first thank you in advance for your help. I have two routers connected via a point to point T1 through an ISP. For redundancy and load ballancing (outgoing and incoming), I will be adding another T1 (which might also be scaled up to 2 T3's). My question is, will multilink PPP work if the serial interfaces have an IP address assigned to them? Experience and reading all say to use virtual templates referencing a loopback or IP Unnumbered (Ethernet) interface to accomplish this? Not using either of the two, is there a way to use MP on serial interfaces that have existing IP addresses? The only other solution is to set up two equal cost default routes for outgoing traffic and use BGP (not an option) for incomming. Any assistance you can provide will be most helpful.

New Member

Re: Multilink PPP on T1's/T3's


1. You could do the loadbalancing/sharing/redundancy on a lower level. Lets say you using a MUX to handle your n x T1/E1:s.

2. Using MPP and multilink interface is the better way (i think).

Setting the IP adress on the multilink interface on each side and make every T1 to join the multilink group.

3. Using the routing protocol and for example the fast-forwarding, route-cache handle the per packet balancing.

This depends on whichtraffic, router, routing protocol and interface configuration you run.

How-to MPP:

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