Frame Relay between Cisco and non-Cisco routers

When configuring Frame Relay there are lots of things that could be asked of you. Imagine a scenario where you are tasked with configuring FR to interact with non-Cisco routers, what do you do?

The first thing some people would think of is LMI, however this probably isn't correct. If you think about it LMI is only locally significant and the routers on either end have no need to match on LMI. Remember that your LMI needs to match the LMI on the Frame Relay switch, that's it.

In the following topology [R1-s0/0---s0/0-FrameSwitch-s0/1---s0/0-R2] the FR switch could be configured so that s0/0 to R1 uses an LMI type of cisco, while the s0/1 to R2 uses q933a. This is a perfectly valid configuration and has no impact on the communication between R1 & R2. If the LMI type doesn't matter, what do we need to change in order to get this to work?

On Cisco routers the default frame-relay encapsulation type is "cisco". If you are running a Cisco router on one end, and a non-Cisco router on the other end, an encapsulation type of "cisco" just wont work. To resolve this issue all you need to do is change the encapsulation type from cisco to ietf. You can configure ietf encapsulation on a per-interface or a per PVC basis as follows

Interface configuration



Interface (interface-dlci)



and finally ietf using frame-relay maps



Remember, when you get stuck the Cisco DocCD is your friend :)