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New Member

Two T1 lines and multilink PPP question

We are getting an additional full T1 line from our ISP for failover and increased bandwith. Each T1 line will go to different NOCs. We decided on multilink ppp (MLPPP). Our ISP told us that traffic will be transmitted on both T1 lines. Packets from one NOC will go to the other NOC, reassembled and send to WAN. In the event one NOC fails, all traffic will go through the other one.

I understand two MLPPP lines must terminate on a single router at a single location. Is what I mentioned above possible?

I also have a 2651XM router with 256MB of memory. I need two seperate WIC CSU/DSU integrated T1 modules. Can someone recommend a model?


Hall of Fame Super Gold

Re: Two T1 lines and multilink PPP question


They might use some kind of vpdn to achieve multichassis multilink ppp.

You can use WIC-1DSU-T1-V2 to terminate the circuits.

Hope this helps, please rate post if it does!

Hall of Fame Super Silver

Re: Two T1 lines and multilink PPP question

The most common implementation is indeed MLPPP which terminates multiple PPP links on the same end devices. There is also an implementation of multi-chassis multilink which can terminate ppp links on separate chassis. I guess that is is possible that the chassis could be in separate NOCs. I have no experience with this implementation where the participating routers are in different NOCs, but I assume that it could work.



New Member

Re: Two T1 lines and multilink PPP question

Thanks for both responses!

Should we concerned about latency since packets has to travel from one NOC to other and reassembled?


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