FA ITN 2022

Choose the role of the ARP Command?

• It resolves MAC addresses to corresponding IP addresses

• It resolves IPv4 addresses to corresponding IPv6 addresses

• Maps a network layer protocol address to a transport layer

• None of the above

Answer explanation

The purpose of ARP is to determine the destination MAC address, the device uses ARP.

ARP provides two basic functions:

• Resolving IPv4 addresses to MAC addresses

• Maintaining a table of mappings

• Maps a network layer protocol address to a data link layer address

Select the process used to place one message inside another message for transfer from the source to the destination.

• Decoding

• Encapsulation

• Flow Control

• Access Control

Answer explanation

Putting the letter into the addressed envelope is called encapsulation.

Each computer message is encapsulated in a specific format, called a frame, before it is sent over the network.

A frame acts like an envelope providing destination address and source address.

Identify what happens if a new ARP request is sent and the switching table already has the addresses in the mac-table?

• It will rebroadcast anyways

• The switch will forwards the frame out of all ports

• It will send to the port number associated with the MAC Address

• None of the above

Answer explanation

If the IP address to be resolved is for this host, then the ARP module updates its ARP cache with the source Ethernet MAC address to source IP address mapping present in the ARP request packet.

If the address is in the table, the frame is forwarded out the port associated with the MAC address in the table.

If the entry is already present in the cache, it is overwritten.

Identify the CORRECT device which stores the MAC address when the ARP command resolves the MAC address.

• Router

• Switch

• Hub

• Brouter

Refer to Figure A8. Identify the function of A & B.

• Contains the frame payload and identifies flow control services.

• Identifies beginning and end of frame and identifies flow control services.

• Used for determine transmission errors and identifies flow control services.

• Indicates source and destination nodes and used for determining transmission errors.

Answer explanation

Select the THREE (3) layers of the OSI model that are comparable in function to the application layer of the TCP/IP model.

i. Presentation

ii. Application

iii. Transport

iv. Session

• i, ii, and iii

• i, ii, and iv

• i, iii, and iv

• ii, iii, and iv

Answer explanation

A

P

S

T

N

D

P

State FOUR (4) basic requirements of a reliable network. [2 marks]

Answer explanation

There are four basic characteristics that the underlying architectures need to address to meet user expectations:

-Fault Tolerance

-Scalability

-Quality of Service (QoS)

-Security