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New Member

Interop of Cisco1600 and Lucent/Ascend Pipeline over FR

Has anyone encountered issues in connecting a Cisco router to an Ascend Pipeline router over FR? I am seeing very strange issues. The link comes up, line protocol is up, but I don't seem to be able to get unicast traffic across the link. Broadcast traffic seems to be OK - or at least the Cisco router is able to receive routing updates from the Pipeline. Pings from the Pipeline are seen by the Cisco router and responded to, but the Pipeline doesn't recognize the responses. Looks to me like there may be some sort of FR header format difference, but I haven't found any reference to an issue like this.

Any help is greatly appreciated.....


New Member

Re: Interop of Cisco1600 and Lucent/Ascend Pipeline over FR

There are two frame relay encapsulation types on a Cisco router - Cisco and IETF. I believe that Cisco is on by default so you may need to change it with interface subcommand

encapsulation frame-relay ietf

But then again, you said that protocol was up so I'm not sure if that is an issue for you.

Remember also about mapping. On all but point-to-point FR subinterfaces, Cisco uses Inverse ARP to establish mappings. Don't know what the Ascend does.

Static maps to your distant router, if required, are configured with interface subcommand

frame-relay map protocol protocol-address dlci broadcast ietf

(ex: frame-relay map ip 10 broadcast ietf, where .1 is the ip of your physical FR interface on the distant end)


show frame-relay map

command will tell you if you already have a map to the distant end.

Can't help you with the config on your Ascend router. Sorry.


New Member

Re: Interop of Cisco1600 and Lucent/Ascend Pipeline over FR


Thanks for the help... I had forgotten about the ietf encapsulation. That seems like it may be the issue since the Cisco router seems to understand everything coming from the Ascend router, but the Ascend doesn't seem to be able to understand packets from the Cisco router. Probably isn't receiving broadcasts either, but I haven't been able to check to see if it has updated it's routing table from dynamic routing or if there is a static pointing to the far end.

Thanks again,


New Member

Re: Interop of Cisco1600 and Lucent/Ascend Pipeline over FR


Hope it works out for you. Please let me know.