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Bridging a T1 to Ethernet?

I have a cheap ISR that I want to use as a "poor mans T1 to Ethernet bridge". I have only one public Internet address with a /30 mask. Handoff is a T1 - until the ISP gets the Ethernet handoff installed...

I want to give this address to the outside interface of an ASA and connect it via crossover to the Ethernet interface of a 1700 router. The T1 WIC will be connected to a router. Can I make the router bridge the WAN to the ASA interface without using an IP address on it? Seems like I have seen somethign similar before...


  • WAN Routing and Switching
Hall of Fame Super Silver

Re: Bridging a T1 to Ethernet?


I don't know if I understand your request.

You can bridge ethernet frames over a T1 WAN link but in order to deliver them at a remote end ethernet LAN port on another router.

How can an ethernet frame be compared with an HDLC or PPP frame ? They are different.

It is easier and possible to route between the T1 link and the ethernet where is the ASA. Of course you will need to modify ASA configuration but it shouldn't be so difficult you will need to change the default-route ip next hop.

Hope to help