Fundamentals of IPv4 Addressing and Routing

Question 1

Each router keeps an IP ______ ______. This table lists IP address groupings, called IP networks and IP subnets.

Answer 1

routing table

Question 2

IP __________ __________ _________ dynamically learns the data link address of an IP host connected to a LAN.

Answer 2

Address Resolution Protocol (ARP)

Question 3

An ___ _____ is any device that has at least one interface with an IP address can send and recieve IP packets.

Answer 3

IP host

Question 4

The term ______ is just a vendorneutral term for byte.

Answer 4

octet

Question 5

Each ______ has four decimal octets, seperated by periods.

Answer 5

Dotted-deciamal notation (DDN)

Question 6

The range of decimal numbers in each octet is betweeen __ and ____

Answer 6

0 and 255

Question 7

True or False

All IP address in the same group must not be seperated from each oter by a router.

Answer 7

True

Question 8

True or False

IP address seperated from each other by a router must be in different groups

Answer 8

True

Question 9

Class A gets roughly half of the IPv4 address space, with all DDN numbers that begin with?

Answer 9

1-126

Question 10

Class B gets one-fourth of the address space, with all DDN numbers that begin with?

Answer 10

128-191

Question 11

Class C gets one-eighth of the address space, with all numbers that begin with?

Answer 11

192-223

Question 12

The _______ ______ is just one reserved DDN value per network that identifies the IP network.

Answer 12

Network Identifier (network ID)

Question 13

With Class C networks and addresses, the first ____ octets define the group.

Answer 13

three

Question 14

With Class A networks and addresses, the ____ octet defines the group.

Answer 14

first

Question 15

With Class B networks and addresses, the first ____ octets define the group.

Answer 15

two

Question 16

What is the first step of the Router Forwarding Logic?

Answer 16

Step 1. Use the data link Frame Check Sequence (FCS) field to ensure that the frame had no errors; if errors occured, discard the frame.

Question 17

What is the second step of the Router Forwarding Logic?

Answer 17

Step 2. Assuming that the frame was not discarded at Step 1, discard the old data link header and trailer, leaving the IP packet.

Question 18

What is the third step of the Router Forwarding Logic?

Answer 18

Step 3. Compare the IP packet’s destination IP address to the routing table, and find the route that best matches the destination address. This route identifies the outgoing interface of the router, and possibly the next-hop router IP address.

Question 19

What is the fourth step of the Router Forwarding Logic?

Answer 19

Step 4. Encapsulate the IP packet inside a new data link header and trailer, appropriate for the outgoing interface, and forward the frame.

Question 20

TCP/IP defines the _______ ________ ________ as the method by which any host or router on a LAN can dynamically learn the MAC address of another IP host or router on the same LAN.

Answer 20

Address Resolution Protocol (ARP)

Question 21

ARP defines a protocol that includes the ARP Request, which is a message that asks the simple request ___________.

Answer 21

“if this is your IP address, please reply with your MAC address”

Question 22

Which of the following are funtions of OSI Layer 3 protocols? (choose two)

a. Logical addressing
b. Physical addressing
c. Path selection
d. Arbitration
e. Error recovery

Answer 22

a. Logical addressing

c. Path selection

Question 23

Imagine that PC1 needs to send some data to PC2, and PC1 and PC2 are separated by several routers. Both PC1 and PC2 sit on different Ethernet LANs. What are the larger entities (in size) that make it from PC1 to PC2? (choose two)

a. Frame
b. Segment
c. Packet
d. L5 PDU
e. L3 PDU
f. L1 PDU

Answer 23

c. Packet

e. L3 PDU

Question 24

Which of the following is a valid Class IP address that can be assigned to a host?

a. 1.1.1.1
b. 200.1.1.1
c. 128.128.128.128
d. 224.1.1.1

Answer 24

b. 200.1.1.1

Question 25

What is the assignable range of values for the first octet for Class A IP networks?

a. 0 - 127
b. 0 - 126
c. 1 - 127
d. 1 - 126
e. 128 - 191
f. 128 - 192

Answer 25

d. 1 - 126

Question 26

PC1 and PC2 are on two different Ethernet LANs that are seperated by an IP router. PC1’s IP address is 10.1.1.1, and no subnetting is used. Which of the following addresses could be used for PC2? (Choose two)

a. 10.1.1.2
b. 10.2.2.2
c. 10.200.200.1
d. 9.1.1.1
e. 225.1.1.1
f. 1.1.1.1

Answer 26

d. 9.1.1.1

f. 1.1.1.1

Question 27

Imagine a network with two routers that are connected with a point-to-point HDLC serial link. Each router has an Ethernet, with PC1 sharing the Ethernet with Router1 and PC2 sharing the Ethernet with Router2. When PC1 sends data to PC2, which of the following is true?

a. Router1 strips the Ethernet header and trailer off the frame received from PC1, never to be used again
b. Router1 encapsulates the Ethernet frame inside an HDLC header and sends the frame to Router2, which extracts the Ethernet frame for forwarding to PC2.
c. Router1 strips the Ethernet header and trailer off the frame received from PC1, which is exactly re-created by Router 2 before forwarding data to PC2.
d. Router1 removes the Ethernet, IP, and TCP headers and rebuilds the appropriate headers before forwarding the packet to Router2.

Answer 27

a. Router1 strips the Ethernet header and trailer off the frame received from PC1, never to be used again

Question 28

Which of the following does a router normally use when making a decision about routing TCP/IP packets?

a. Destination MAC address
b. Source MAC address
c. Destination IP address
d. Source IP address
e. Destination MAC and IP address

Answer 28

c. Destination IP address

Question 29

Which of the following are true about a LAN-connected TCP/IP host and its IP routing (forwarding) choices? (choose two)

a. The host always sends packets to its default gateway.
b. The host sends packets to its default gateway if the destination IP address is in a different class of IP network than the host
c. The host sends packets to its default gateway if the destination IP address is in a different subnet than the host
d. The host sends packets to its default gateway if the destination IP address is in the same subnet as the host

Answer 29

b. The host sends packets to its default gateway if the destination IP address is in a different class of IP network than the host
c. The host sends packets to its default gateway if the destination IP address is in a different subnet than the host

Question 30

Which of the following are functions of a routing protocol? (choose two)

a. Advertising known routes to neighboring routers
b. Learning routes for subnets directly connected to the router
c. Learning routes, and putting those routes into the routing table, for routes advertised to the router by its neighboring routers
d. Forwarding IP packets based on a packet’s destination IP address

Answer 30

a. Advertising known routes to neighboring routers
c. Learning routes, and putting those routes into the routing table, for routes advertised to the router by its neighboring routers

Question 31

A company implements a TCP/IP network, with PC1 sitting on an Ethernet LAN. Which of the following protocols and features requires PC1 to learn information from some other server device?

a. ARP
b. ping
c. DNS
d. None of the other answers are correct

Answer 31

c. DNS