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Redundant T1s from North America to Europe


My first time setting up such a WAN configuration, appreciate any/all advice.

The requirement is to have redundant T1 links (min of 256k for data) between a site in N-A and a site in Europe. No need to aggregate, just to have redundant paths in case one circuit goes down.

choice of router:

Cisco 1841 at each site, each with 2 WICs (one for each T1 circuit)

choice of modules:

N-America = WIC-1DSU-T1-V2

Europe = what is the T1/E1 equivalent? similar to configure?

T1/256k configuration at each site:

- do I use channels 1 to 4 (on each T1 link/module) if I only require a total of 256k?

WAN redundancy:

- how do I setup data flow to automatically route/fail-over from one T1 circuit to the other? (just using static routes, unless routing protocol necessary?)

Appreciate the assistance.


Re: Redundant T1s from North America to Europe


your module can be the VWIC-2MFT-E1 or the likes for your european side.

the configuration will be 'similar' but not exaclty the same as the E1 requires different signaling, framing, etc.

(you do need to work with the provider in order to assure your E1 channels map to your T1 correctly or you will not be able to get the link(s) up correctly.)

please see the following link for more E1 configuration info:


YES, if you only needed the 256k and you were sure of the channels the provider is sending you, then 1-4 would be correct.

(the issue here is to be sure what channels the provider is sending you to use. if the entire 24 channels are available, then 1-4 would be fine; of course 20-23 would work as well)


the easiest way to setup these two links for redundancy is to use EIGRP or OSPF routing protocols. these will automatically form redunant paths to your destination. if one link fails, the other takes over automatically. eigrp & ospf can hold upto 6 paths to a single destination in their routing tables.

please see the following links for more eigrp & ospf configuration info:

eigrp -

ospf -