CISCO CCNA Exam – Q333

Which two statistics appear in “show frame-relay map” output? (Choose two.)

A. the number of BECN packets that are received by the router
B. the value of the local DLCI
C. the number of FECN packets that are received by the router
D. the status of the PVC that is configured on the router
E. the IP address of the local router

Correct Answers: B,D

Sample “show frame-relay map” output:
R1#sh frame map
Serial0/0 (up): ip dlci 401(0x191,0x6410), dynamic,
broadcast,, status defined, active
Serial0/0 (up): ip dlci 403(0x193,0x6430), dynamic,
broadcast,, status defined, active
Serial0/0 (up): ip dlci 401(0x191,0x6410), static,
CISCO, status defined, active

CISCO CCNA Exam – Q251

Refer to the exhibit.
CISCO CCNA Exam – Q251

What is the meaning of the term dynamic as displayed in the output of the show frame-relay map command shown?

A. The Serial0/0 interface is passing traffic.
B. The DLCI 100 was dynamically allocated by the router.
C. The Serial0/0 interface acquired the IP address of from a DHCP server.
D. The DLCI 100 will be dynamically changed as required to adapt to changes in the Frame Relay cloud.
E. The mapping between DLCI 100 and the end station IP address was learned through Inverse ARP.

Correct Answer: E

Inverse Address Resolution Protocol (Inverse ARP) was developed to provide a mechanism for dynamic DLCI to Layer 3 address maps. Inverse ARP works much the same way Address Resolution Protocol (ARP) works on a LAN. However, with ARP, the device knows the Layer 3 IP address and needs to know the remote data link MAC address. With Inverse ARP, the router knows the Layer 2 address which is the DLCI, but needs to know the remote Layer 3 IP address.

When using dynamic address mapping, Inverse ARP requests a next-hop protocol address for each active PVC. Once the requesting router receives an Inverse ARP response, it updates its DLCI-to-Layer 3 address mapping table. Dynamic address mapping is enabled by default for all protocols enabled on a physical interface. If the Frame Relay environment supports LMI autosensing and Inverse ARP, dynamic address mapping takes place automatically. Therefore, no static address mapping is required.