Question 1 | CHAP requires which of the following to be configured? [Choose the two best answers.] |
A1: | Answer: C, E . CHAP requires PPP and the username to be configured to allow for authentication. |
Question 2 | Which ISDN command will bring up the second B channel when the first has reached a load of approximately 50 percent? |
A2: | Answer: C . The dialer load-threshold 125 command will bring up the second B channel when the first reaches approximately 50 percent load. The command will accept a value of 1 to 255, with 1 being the lowest load and 255 being 100 percent load. |
Question 3 | To verify all three layers of an ISDN circuit prior to dialing, an administrator should use which of the following commands? -
A. show ppp multilink -
B. debug ppp -
C. debug bri -
D. show run -
E. show isdn status |
A3: | Answer: E . The show isdn status command provides the connection status of all three layers, as well as calls in progress. |
Question 4 | Which of the following is a valid North American SPID? -
A. 172.16.1.1 -
B. 800.555.1.002 -
C. 300.106 -
D. 5551002 -
E. 91655510020100 |
A4: | Answer: E . The SPID is the complete phone number, including the area code, plus a 4-digit value added to the 7-digit dialer number, without punctuation. Some service providers add an additional two digit prefix to the number. However, the only valid answer above would be E. |
Question 5 | If you have a newly configured router and an ISDN call succeeds, but pings and other packets fail, which of the following can be the cause? [Choose all that apply.] |
A5: | Answer: A, B, C , and D . All of these causes are possibilities and should be checked. E is incorrect, because if the cable were faulty, the call would not succeed. |
Question 6 | If an ISDN router will not dial, which of the following is the likely problem? [Choose all that apply.] |
A6: | Answer: F . All of these are possible causes of why the router will not dial. |
Question 7 | Which of the following are advantages of using CHAP authentication? [Choose the two best answers.] -
A. Password authentication -
B. Password encryption -
C. Compression and encryption of data packets -
D. Virtual LANs are attached to ISDN switched connections |
A7: | Answer: A, B . CHAP is used for password authentication, and encrypts the password for more secure connections. |
Question 8 | Which of the following two command prompts can execute the isdn switch-type command? -
A. User mode command prompt -
B. Privilege EXEC Mode command prompt -
C. Global configuration mode command prompt -
D. Interface configuration mode command prompt |
A8: | Answer: C, D . You can use the isdn switch-type command in the global or interface configuration modes. |
Question 9 | ISDN Basic Rate Interface (BRI) provides which of the following? -
A. Two 64Kbps B channels and one 16Kbps D channel -
B. Total bit rate of up to 768Kbps -
C. Two 56Kbps B channels for data -
D. 10Mbps on two channels and a third for control using 192Kbps |
A9: | Answer: A . ISDN BRI provides B channels for data (64Kbps each) and one D channel (16Kbps) for clocking and control. |
Question 10 | Which one of the following ISDN-specific protocols is used to establish a Layer 2 connection? -
A. q.921 -
B. PPP -
C. CHAP -
D. q.931 -
E. Ethernet |
A10: | Answer: A . The q.921 protocol is used for Layer 2 connections. CHAP and PPP are not specific to ISDN. Ethernet is a Layer 1 topology, and q.931 is used for call connection establishment at Layer 3. |
Question 11 | On certain routers, if the switch type is unknown, which one of the following commands should you use? |
A11: | Answer: E . The isdn autodetect command instructs the router to detect the switch type. The other commands are all invalid commands. |