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Using 1720 as bridges

I need some help turning my 1720's into bridges so I can have two nodes on the same subnet on different sides of the routers. Are there any good places on the web to learn how to do this? We are using 1720's with 56k 4-wire circuit WIC's to communicate with a GE wind turbine 50 miles away. The turbine PC's IP is and the Control PC's IP has to be

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Re: Using 1720 as bridges


first of all I would check again with the turbine maintainer if they would allow the PC to be on a different subnet, that would allow you a regular routed setup that has major advantages.

This said if not possible, on both routers, in global configure "no ip routing", "bridge 1 protocol ieee" then under both serial and ethernet "bridge-group 1". Give two IP addresses from the same subnet to serial and ethernet. These are needed so you can telnet into the routers to check on things. That's it.

Hope this helps, please rate post if it does!

Re: Using 1720 as bridges

If you want both your 1720's to function as simply as a bridge then a configuration similar to this one on both routers is all you need. I assume both 1720's are dedicated for this function and doesn't handle other traffic in your network.

no ip routing

int f0

bridge-group 1

int s0

bridge-group 1

bridge 1 protocol ieee

Have a look at this link. Look under transparent bridging.