Explanation/Reference:
Cisco Frame Relay Configurations
Reference:
http://www.ciscopress.com/articles/article.asp?p=170741&seqNum=2
Explanation:
Cisco supports two different Frame Relay encapsulation types. The default Frame Relay encapsulation enabled on supported interfaces is the Cisco encapsulation. Cisco also supports the IETF Frame Relay encapsulation type, which is in conformance with RFC 1490 and RFC 2427. RFC 2427 supercedes RFC
1490. Both RFC specifications define standards allowing multiple routed protocols to be carried over Frame Relay.
You can test with your Cisco router by typing the command Router(config-if)#encapsulation frame-relay ?
on a WAN link. Note: Three LMI options are supported by Cisco routers are ansi, Cisco, and Q933a. They represent the ANSI Annex D, Cisco, and ITU Q933-A (Annex A) LMI types, respectively. HDLC is a WAN protocol same as Frame-Relay and PPP so it is not a Frame Relay encapsulation type.
