1000 CCNA Interview Questions Answers4

50 Which addresses are INCORRECTLY paired with their class?

A. 1 to 126, Class A

B. 128 to 191, Class A C. 1 to 126, Class B

D. 128 to 191, Class B

Ans:B & C.

Address classes are: 1 to 126, Class A; 128 to 191, Class B, 192 to 223, Class C; 224 to 239, Class D; and

240 to 255, Class E. The first octet rule states that the class of an address can be determined by the numerical value of the first octet

51 Which addresses are INCORRECTLY paired with their class?

A. 240 - 255, Class D B. 240 - 255, Class E C. 224 - 239, Class D

D. 224 - 239, Class E

Ans A & D

Address classes are: 1 to 126, Class A; 128 to 191, Class B, 192 to 223, Class C; 224 to 239, Class D; and 240 to 255, Class E.

52 Which IP Address Class is INCORRECTLY paired with its range of network numbers?

A. Class A addresses include 192.0.0.0 through 223.255.255.0

B. Class A addresses include 1.0.0.0 through 126.0.0.0

C. Class B addresses include 128.0.0.0 through 191.255.0.0

D. Class C addresses include 192.0.0.0 through 223.255.255.0

E. Class D addresses include 224.0.0.0 through 239.255.255.0

Ans A

Class A addresses include 1.0.0.0 through 126.0.0.0

Class B addresses include 128.0.0.0 through 191.255.0.0

Class C addresses include 192.0.0.0 through 223.255.255.0

Class D addresses include 224.0.0.0 through 239.255.255.0

53 Which IP Address Class can have 16 million subnets but support 254 hosts?

A. Class C B. Class A

C. Class B

D. Class D

Ans A

Possible Subnets IP Address Class Possible Hosts

254 A 16M.

64K B 64K

16M C 254

54 Which IP Address Class can have 64,000 subnets with 64,000 hosts per subnet?

A. Class B B. Class A

C. Class C D. Class D

Ans A

IP Address Class Possible Subnets Possible Hosts

254 A 16M

64K B 64K

16M C 254

55 There are two processes to pair MAC address with IP addresses. Which process finds an IP address from a MAC address?

A. RARP

B. ARP C. RIP D. IGRP

Ans A

ARP (Address Resolution Protocol) maps an IP address to the MAC address, RARP (Reverse Address Resolution Protocol) maps the MAC address to the IP address. ARP and RARP work at the internet layer of the Internet Model or the network layer of the OSI model.

56 When the router runs out of buffer space, this is called                _.

A. Source Quench

B. Redirect

C. Information Request

D. Low Memory

Ans A

Source quench is the process where the destination router, or end internetworking device will

"quench" the date from the "source", or the source router. This usually happens when the destination router runs out of buffer space to process packets.

57 Which protocol carries messages such as destination Unreachable, Time Exceeded,

Parameter Problem, Source Quench, Redirect, Echo, Echo Reply, Timestamp, Information

Request, Information Reply, Address Request, and Address Reply?

A. ICMP B. UDP C. TCP

D. TFTP

E. FTP

Ans A

ICMP (Internet Control Message Protocol) is a network layer internet protocol described in RFC #

792. ICMP reports IP packet information such as destination Unreachable, Time Exceeded, Parameter Problem, Source Quench, Redirect, Echo, Echo Reply, Timestamp, Information Request, Information Reply, Address Request, and Address Reply.

58 Two of the protocols that can be carried in the Protocol field of an IP packet are?

A. TCP B. UDP

C. FTP D. TFTP

Ans A & B

The following are the fields in an IP segment, their length, and their definitions:

VERS (Version number - 16 bits)

HLEN (Number of 32-bit words in the header - 4 bits)

Type of Server (How the datagram should be handled - 32 bits) Total Length (Total length of header and data - 32 bits)

Identification (Provide fragmentation of datagrams to allow different MTUs in the internet - 4 bits) Flags (Provide fragmentation of datagrams to allow different MTUs in the internet - 4 bits)

Frag Offset (Provide fragmentation of datagrams to allow different MTUs in the internet - 6 bits) TTL (Time-To-Live - 6 bits)

Protocol (Upperlayer protocol sending the datagram - 16 bits)

Header Checksum )Integrity check on the header - 16 bits) Source IP Address (32 bits)

Destination IP Address (32 bits)

IP Options (network testing, debugging, security and others - 4 bits) Data (4 bits).

59 Where would network testing be included in an IP packet?

A. IP Options field

B. Identification field

C. Type of Service field

D. Reservation field

Ans A

The following are the fields in an IP segment, their length, and their definitions: VERS (Version number - 16 bits)

HLEN (Number of 32-bit words in the header - 4 bits)

Type of Server (How the datagram should be handled - 32 bits) Total Length (Total length of header and data - 32 bits)

Identification (Provide fragmentation of datagrams to allow different MTUs in the internet - 4 bits) Flags (Provide fragmentation of datagrams to allow different MTUs in the internet - 4 bits)

Frag Offset (Provide fragmentation of datagrams to allow different MTUs in the internet - 6 bits) TTL (Time-To-Live - 6 bits)

Protocol (Upperlayer protocol sending the datagram - 16 bits) Header Checksum )Integrity check on the header - 16 bits)

Source IP Address (32 bits) Destination IP Address (32 bits)

IP Options (network testing, debugging, security and others - 4 bits) Data (4 bits).

60 What field tells the Internet layer how to handle an IP packet?

A. Type of Service

B. Identification

C. Flags

D. Frag Offset

Ans A

The following are the fields in an IP segment, their length, and their definitions: VERS (Version number - 16 bits)

HLEN (Number of 32-bit words in the header - 4 bits)

Type of Server (How the datagram should be handled - 32 bits) Total Length (Total length of header and data - 32 bits)

Identification (Provide fragmentation of datagrams to allow different MTUs in the internet - 4 bits) Flags (Provide fragmentation of datagrams to allow different MTUs in the internet - 4 bits)

Frag Offset (Provide fragmentation of datagrams to allow different MTUs in the internet - 6 bits)

TTL (Time-To-Live - 6 bits)

Protocol (Upperlayer protocol sending the datagram - 16 bits) Header Checksum )Integrity check on the header - 16 bits) Source IP Address (32 bits)

Destination IP Address (32 bits)

IP Options (network testing, debugging, security and others - 4 bits) Data (4 bits).