Difference between using subinterfaces and using FR Map?

Admittedly I don't work with frame relay very much, so my understanding may be a bit sub par. Essentially I want to know what the differences are between using subinterfaces and using frame relay map commands? I've seen hub/spoke networks set up using both, and both support the broadcast command, so what gives? Is it just two ways of doing it? is one way better than the other?

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EdTheLad

A quick reply as im busy testing, a subinterface can be either p2p or multipoint.A p2p subinterface doesnt use the map command, you just specify the dlci using "interface-dlci".If you are using a multipoint subinterface it behaves like a regular physical interface, you can use either inverse-arp or disable inverse-arp.If you wanna use inverse arp you must specify the dlci that is on the subinterface using "interface-dlci" and let arp take care of the mapping.If you wanna disable inverse-arp, use the "frame-relay-map" command.

Paul Boz

Why would you want to disable ARP and use the frame relay map command? overhead?

EdTheLad

Security and stability, to be in control of your mappings.If you had a customer hanging off your FR cloud you wouldn't want them to effect your local mappings with their bad config.

Paul Boz

Right, thank you for the clarification. In fact, since I have your attention, can you recommend a quality book on frame relay?

Thanks Ed.

EdTheLad

I can't really think of anything off hand, i usually use multiple books as i've got hundreds of ebooks to search through.If you can get your hands on a BCRAN knowledgenet or Cisco training academy course notes it would be a good start.

Pash

http://www.amazon.com/Cisco-Certification-Bridges-Routers-Switches/dp/0130903892/ref=sr_1_3/002-1202226-9508043?ie=UTF8&s=books&qid=1180949717&sr=8-3 - as reccommended by Turgon, i will pick myself up a copy when im back onto Cisco.