思科认证考试（ＣＣＮＡ）考试模拟题４０—５９及答案

    

48. [OxNx] Frames are converted to Bits at which layer? 

a) Application Layer 7 
b) Presentation Layer 6 
c) Session Layer 5 
d) Transport Layer 4 
e) Network Layer 3 
f) Data Link Layer 2 
g) Physical Layer 1 

49. [OxNx] Which of the following could be a feature of a connection-oriented service? 

a) Flow Control 
b) "Three-Way" hand shake 
c) Error checking 
d) Windowing 
e) All of the above 

50. [OxNx] With a connection-oriented service a host will ACK (Acknowledge) with: (Answer all that apply) 

a) The last (SEQ) sequence number received from the remote host 
b) The next expected (SEQ) sequence number from the remote host 
c) The last ACK number from the remote host 
d) The current SEQ number from the remote host "plus" 1 
e) None of the above 

51. [OxNx] Simple Network Management Protocol uses what numeric value, in decimal, of the destination port field of the User Datagram Protocol (UDP) header? 

a) 20 
b) 21 
c) 23 
d) 69 
e) 161 

52. [OxNx] The first segment of the "Three-Way Handshake" will most likely carry an ACK of (Choose the best answer): 

a) 1 
b) The SEQ number of the remote host "plus" 1 
c) 0 
d) There is no ACK. 
e) A randomly generated number 

53. [OxNx] Which one of the following layers "best" describes the ability of the upper layers to gain independence over LAN media access? 

a) Application Layer 7 
b) Presentation Layer 6 
c) Session Layer 5 
d) Transport Layer 4 
e) Network Layer 3 
f) Data Link Layer 2 
g) Physical Layer 1 
h) MAC sublayer 
i) LLC sublayer 

54. [OxNx] The Media Access Control (MAC) address is made up of the following two parts. 

a) Vendor Code 
b) Network Address 
c) Host Address 
d) Serial Number 
e) No such address 

55. [OxNx] Which one of the following describes the process of a TCP/IP host learning a remote host MAC address? 

a) ARP (Address Resolution Protocol) 
b) SLARP (Serial Line Address Resolution Protocol) 
c) RARP (Reverse Address Resolution Protocol) 
d) IARP (Inverse Address Resolution Protocol) 
e) MOP (Maintenance Operation Protocol) 

56. [OxNx] What is the major difference between the Ethernet version 2 frame and the 802.3 frame? 

a) 802.3 frame uses a two-byte Length field where Ethernet describes type. 
b) 802.3 frame uses a two-byte field for sequence numbers where Ethernet describes Type. 
c) Ethernet uses a 802.2 header to describe type. 
d) Ethernet uses a SNAP header. 
e) There is no major difference. 
f) None of the above. 

57. [OxNx] What is the purpose of the 802.3 Subnet Access Protocol (SNAP) format? 

a) To make ethernet perform faster 
b) To identify the length of the frame 
c) To identify proprietary protocols 
d) To allow windowing 
e) To allow flow control 

58. [OxNx] When a Destination Service Access Point (DSAP) and Source Service Access Point (SSAP) are set to AA: 

a) All stations with AA contained in their MAC addresses would receive this frame. 
b) All stations would receive this frame, because it acts like a broadcast. 
c) The encapsulated protocol contained in the frame must be IP. 
d) The encapsulated protocol contained in the frame is proprietary. 
e) None of the above. 

59. [RINx] What Cisco feature of RIP will reduce convergence time? 

a) Cisco uses full horizons as opposed to split horizons 
b) The hold down timer is not activated 
c) Event triggered updates are used 
d) Infinity is 10 instead of 16 
e) There is no Cisco feature to enhance the performance of IP RIP