Frame Relay

1. You have a total of five routers. ________ circuits are required to fully mesh the network, where every router needs ___________ interfaces.

A. 5, 5

B. 8, 4

C. 10, 5

D. 10, 4

Answer: D

Use the (N*(N – 1)/2) formula for the number of circuits. You need a total of ten circuits and four interfaces on each router.

A has the wrong number of circuits and interfaces. B has the wrong number of circuits.

C has the wrong number of interfaces.

2. A ___________ is similar to a telephone circuit-switched connection.

A. PVC

B. SVC

Answer: B

An SVC is similar to a telephone circuit-switched connection.

A is similar to a leased line.

3. You have a 24-channel T1 connection to your router. How many VCs does this T1 support?

A. 1

B. 24

C. No limit

Answer: C

The number of VCs is not tied to any physical properties of a connection type. Remember that VCs are logical connections.

A would be true if this were a leased line. B refers to the number of time slots in a T1 and has no effect on the number of VCs a connection can support.

4. _________ defines how the Frame Relay DTE and DCE interact with each other.

A. DLCI

B. CIR

C. LMI

D. PMI

Answer: C

The local management interface (LMI) defines how the Frame Relay DTE and DCE interact with each other.

A defines the local address of a VC. B defines the average traffic rate for a VC. D is a nonexistent acronym.

5. The address of a Frame Relay VC is called a ___________.

A. Data link layer connection identifier

B. Data layer connection index

C. Data link connection index

D. Data link connection identifier

Answer: D

The address of a Frame Relay VC is called a data link connection identifier (DLCI).

A and C include the term layer. B and C use the term index.

6. Frames sent above the __________ limit will have their _________ bit set.

A. CIR, DE

B. BC, DE

C. BC, FECN

D. CIR, FECN

Answer: B

Frames sent above the BC limit will have their DE bit set.

A and D are incorrect because frames sent between CIR and BC are okay. C and D specify FECN, which is used for flow control.

7. When a carrier experiences congestion, it marks the _______ bit in the header of the Frame Relay frame.

A. CIR

B. DE

C. BECN

D. FECN

Answer: D

When a carrier experiences congestion, it marks the FECN bit in the header of the Frame Relay frame.

A specifies the average rate of a VC. B is used to mark frames that exceed their allowable rate. C is marked by the destination device to indicate congestion, and is sent to the source device.

8. Annex A is which LMI standard?

A. Cisco

B. ITU-T Q.933

C. ANSI

Answer: B

The LMI type Annex A is defined by ITU-T Q.933.

A is the Gang of Four. C is Annex D.

9. Cisco routers generate LMI enquiries every _______ seconds and a full status update every _________ seconds.

A. 10, 60

B. 10, 6

C. 60, 300

D. 15, 60

Answer: A

Cisco routers generate LMI enquiries every 10 seconds and a full status update every 60 seconds.

B specifies the wrong update interval for the full update message. C has wrong values for both timers. D has a wrong value for the status enquiry timer.

10. Enter the router command to have the serial interface use a Frame Relay RFC 1490 frame type: ____________.

A. CLICK TO VIEW THE ANSWER

Answer: A

ENCAPSULATION FRAME-RELAY IETF

11. Enter the router command to set the LMI type to ITU-T Annex A: ____________.

A. CLICK TO VIEW THE ANSWER

Answer: A

FRAME-RELAY LMI-TYPE Q933A

12. When using the show interfaces command, which Frame Relay information can you not see?

A. The DLCI number used for LMI

B. The number of LMIs sent and received

C. Statuses of PVCs

D. The LMI type

Answer: C

When using the show interfaces command, you cannot see the statuses of the PVCs—you need to use the show frame-relay pvc command.

A, B, and D can be seen in the output of this command.

13. Which Frame Relay command is used to manually resolve addresses?

A. frame-relay interface-dlci

B. frame-relay map

C. frame-relay resolve

D. frame-relay lmi-type

Answer: B

The frame-relay map command is used to manually resolve layer-3 addresses to DLCIs.

A associates a DLCI to a subinterface. C is a nonexistent command. D hard-codes the LMI type for the physical serial interface.

14. If you see a VC with an inactive status, this indicates ____________.

A. The connection between both Frame Relay DTEs is up and operational.

B. The connection between your Frame Relay DTE and DCE is up and operational, but there is something wrong with connection between your connected Frame Relay switch and the destination DTE.

C. You are not receiving any LMI messages from the Frame Relay switch. Nonbroadcast Multiaccess

Answer: B

If you see a VC with an inactive status, this indicates that the connection between your Frame Relay DTE and DCE is up and operational, but there is something wrong with connection between your connected Frame Relay switch and the destination DTE.

A is an active VC. C is a deleted VC.

15. ________ topologies in NBMA environments do not have problems with split horizon.

A. Partially meshed

B. Fully meshed

C. Hub and spoke

D. Star

Answer: B

Fully meshed topologies in NBMA environments do not have problems with split horizon.

A, C, and D have problems with split horizon.

16. Enter the router command to create a multipoint subinterface on serial0 with a subinterface number of 5: __________.

A. CLICK TO VIEW THE ANSWER

Answer: A

INTERFACE SERIAL 0.5 MULTIPOINT

17. Enter the router command to associate DLCI 500 with a subinterface: ____________.

A. CLICK TO VIEW THE ANSWER

Answer: A

FRAME-RELAY INTERFACE-DLCI 500