Cisco CCNA考试七十九题

来源：作者：出处：巧巧读书 2006-07-25 进入讨论组

　　16. What is an example of a MAC address?

　　A. Az32:6362:2434
　　B. Sj:2817:8288
　　C. GGG:354:665
　　D. A625:cbdf:6525

　　The address is a 48 bit address which

　　requires 12 Hex digits.A hex digit can t be past

　　the letter F. Hex stands for 16. 1-9 and A-F

　　make up numbers that are valid.

　　17. Which of the following is not part of

　　the data link layer?

　　A. Transports data across the physical link
　　B. Performs physical addressing
　　C. Performs flow control
　　D. Determines network topology
　　E. Terminates a session
　　This is part of the session layer

　　18. Which of the following are data link protocols?

　　A. HDLC
　　B. FTP
　　C. SQL
　　D. ISDN
　　E. Token Ring

　　FTP is an application and SQL is a session layer protocol.

　　19. Of the following address AA77:3827:EF54,

which of the following is the vendor portion?

　　A. AA7738
　　B. 27EF54
　　C. AA77
　　D. EF54
　　The vendor code is how you can tell who made the card.

　　The last 6 digits are the physical address.

20. Which of the following are examples of layer 3 addressing?

A. 165.33.4.34
B. AA77:3827:EF54
C. HHHH:hg:7654
D. 76

The first is a TCPIP address and the second is an IPX address

21. What is considered Layer 3 addressing?

A. Data Link Layer
B. Network Layer
C. Application Layer
D. None of these

Physical is Layer 1, then data link, and then Network. This is the same layer

that routers are on.

22. What layer are Bridges on?

A. Data Link
B. Physical
C. Application
D. Transport

Bridges segment networks but are not able to determine addresses like the network layer

does.

23. Repeaters are on what layer?

A. Transport
B. Session
C. Physical
D. Application

All repeaters can do is boost a signal. An active hub is a good example of a repeater.

A switching hub is a good example of layer 3 addressing, since switches go by network

addresses and IPX addresses rather than just boost signals. Bridges can only read mac

addresses, and not the full IPX or TCPIP addresses.

24. Which of the following are considered routing protocols?

A. OSPF
B. IP
C. IPX
D. EIGRP
E. Token Ring

Answers B and C are routed protocols, whereas A and D are

the protocols that do the routing. This is easily confused.

You can remember it by thinking that the routing protocols

that haul the routed protocols are like a tug ship pulling a barge.

The barge is full of data.

25. Which two of the following are considered connection

oriented communication?

A. Setup and maintenance procedures are performed to ensure

message delievery
B. A physical circuit exists between two communicating devices
C. It is a best effort type of communication
D. A virtual connection exists between the two

B is not a necessity, and C is not accurate. TCP is connection oriented

and UDP is not.

26. Which of the following are not WAN protocols? Choose 2

A. Frame Relay
B. ATM
C. Ethernet
D. FDDI
E. ISDN

Ethernet and FDDI are LAN protocols.

27. Which of the following will allow you to view NVRAM s contents?

A. show configuration
B. show protocols
C. show version
D. show running-config
E. show startup-config

Answer A E. These show the backup configuration stored in NVRAM.

The other anwsers allow youto view RAM.

28. Which of the following contains the OS image?

A. Flash
B. NVRAM
C. RAM
D. Interfaces

ROM will be used if Flash is unavailable. NVRAM is the backup

configuration, and RAM is the active configuration

29. Which of the following indicates the router is in privilege mode?

A. Router#
B. Router>
C. Router-
D. Router*

Answer B shows the router in user mode.

30. What does "show cdp neighbors" not show? Neighbors_________

A. device id
B. hardware platform
C. ios version
D. port type and number