Have I figured Frame Relay out yet?

jscimeca715

Let me see if this is correct, as I've been working my @$$ off to get this stuff through my head.

If you have a multipoint connection to a router, by either using the physical interface or multipoint subinterface, you have to use the frame-relay interface-dlci command to tell the router which dlci's can be inverse arped to that IP address.

If you have a point-to-point physical or subinterface, you need the frame-relay interface-dlci command because InverseARP is not available.

Bueller? Bueller? Bueller?

Am I right? Or Am I on the right track?

jscimeca715

Okay, I think I might be narrowing it down. You don't need to specify on physical interfaces because LMI will deliver the PVC's to the physical interface. However, on point-to-point you will need to use frame-relay interface-dlci command and on multi-point you can use either frame-relay interface-dlci (if Inverse ARP is enabled) or frame-relay map ip next-hop ip dlci broadcast (if Inverse ARP is disabled).

Closer?

Neeko

jscimeca715 wrote: »

Okay, I think I might be narrowing it down. You don't need to specify on physical interfaces because LMI will deliver the PVC's to the physical interface. However, on point-to-point you will need to use frame-relay interface-dlci command and on multi-point you can use either frame-relay interface-dlci (if Inverse ARP is enabled) or frame-relay map ip next-hop ip dlci broadcast (if Inverse ARP is disabled).

Closer?

Yes, this sounds correct.

All subinterfaces will require the frame-relay interface-dlci command because there is no other way for the router to know which DLCIs apply to each subinterface.

A physicall interface does not need this because LMI messages contains this information, and since subinterfaces cannot be configured if the physical interface is in use, the frame-relay interface-dlci command is not required.