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New Member

T1's over Internet

trying to eliminate a T1 backhaul line with model 1750 units. Have DSU-t1 units and have it configured for GRE tunnel. The 2 FastEthernet0 interfaces talk to each other, and the T1's show that they are working to the model 1750's, but the T1's seem to cycle and not stay on constantly, plus they do not seem to connect to the tunnel. ??

Any help is appreciated ??


Hall of Fame Super Silver

Re: T1's over Internet


I do not yet understand the issue well enough to suggest a solution. A better description of the topology would be a good place to start. If the 2 FastEthernet interfaces talk to each other, how are they connected? Are they directly connected back to back, connected through a single switch, connected through some Corporat network infrastructure?

And what do the T1s connect to? Are they directly connected router to router? Or do the T1s connect to some provider(s) and the provider(s) provide connectivity between the T1s?

And especially for finding what is going on with the tunnel we would need to see configurations from both routers.

If you can clarify these things we may be able to provide better answers to your issues.



New Member

Re: T1's over Internet

Trying to setup the unit to use it to replace a dedicated t1 leased line. The current T1 circuit is a 24 slot ESF b8zs voice circuit.

There is a Wescom D4 mux unit at each end, with 4 wire cards in it.

What I want to do is replace the T1 circuit with a cisco 1750 at each end, and run the T1 over the Internet.

I can get the FastEthernet0 interfaces to talk to each other, and the T1 DSU cards work to the Wescom Muxs fine. But I can't seem to get the T1 interfaces to talk to the FastEthernet0

interfaces, and then to the other Cisco 1750 unit. So far have tried a GRE tunnel.

FastEthernet0 interfaces will need to use an Internet gateway address, and send to a remote IP address (the remote cisco 1750 unit).

Have all static addresses for it.

Right now I am just setting it up back to back to get it to work before I put it on the Internet and remote it.

Any help is appreciated !!

Software version is 12.1