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1. The first byte of a class-C IP address is in the range of

• A.0-127

• B.128-191

• C.192-223

• D.224-239

Answer explanation

Explanation: In classful addressing, the address space is divided into five classes: A, B, C, D, and E. The first byte of a Class C IP address ranges from 192 to 223.

2. Given a host address of 168.150.3.6/22. Find the broadcast address of the subnet

• A.255.255.252.0

• B.168.150.0.0

• C.168.150.3.255

• D.168.150.0.1

Answer explanation

1. Explanation: In CIDR notation, /22 signifies that the first 22 bits are the network prefix and the remaining bits are used for host addresses. In this case, the broadcast address would be the highest address within the host range. So, for 168.150.3.6/22, the broadcast address is 168.150.3.255.

3. Routing is performed by

• A.layer-2 switches

• B.hubs

• C.NICS

• D.routers

Answer explanation

1. Explanation: Routers are networking devices that forward data packets between networks. Routing is the process of selecting paths in a network along which to send network traffic.

4. How many bits should be borrowed to subnet a network into four subnets ?

• 2

• 3

• 4

• 8

Answer explanation

1. Explanation: To create four subnets, two bits need to be borrowed from the host portion of the address. 2^2 equals 4, which creates four subnets.

5. Which is a valid IPv4 address?

• A.206.133.252.79

• B.192.168.259.97

• C.171.16.270.100

• D.10.111.212.313

Answer explanation

1. Explanation: IPv4 addresses consist of four sets of numbers from 0 to 255, separated by three dots. Thus, 206.133.252.79 is a valid IPv4 address. The rest of the options exceed 255.

6. What is the broadcast address of the network 212.12.12.0/24?

• A.212.255.12.255/24

• B.212.12.12.255/24

• C.212.12.255.255/24

• D.212.255.255.255/24

Answer explanation

1. Explanation: The broadcast address is the last address in the subnet and is used to address all nodes in the network. So for 212.12.12.0/24, the broadcast address is 212.12.12.255.

7. The protocol assigns IP addresses automatically

• A.DHCP

• B.SSH

• C.DNS

• D.HTTP

Answer explanation

1. Explanation: DHCP (Dynamic Host Configuration Protocol) is the protocol that allows hosts to obtain necessary TCP/IP configuration information from a DHCP server.

8. The data unit in the Transport layer is,

• A.Frame

• B.Packet

• C.Segment

• D.Bit

Answer explanation

1. Explanation: In the OSI model, the transport layer receives data from the session layer above it. The transport layer then takes the data and divides it into smaller units known as segments.

9. The data unit in the Network layer is

• A.Frame

• B.Packet

• C.Segment

• D.Bit

Answer explanation

1. Explanation: In the OSI model, the network layer is responsible for receiving frames from the data link layer, and then packaging them into packets for routing.

10. Which organization builds the Wi-Fi standards?

• A.IEEE

• B.JSO

• C.Google

• D.Microsoft

Answer explanation

1. Explanation: The IEEE (Institute of Electrical and Electronics Engineers) develops networking standards, including 802.11, commonly known as Wi-Fi.