Q.1 What is the default subnet mask for a Class B IPv4 address?
255.0.0.0
255.255.0.0
255.255.255.0
255.255.255.255
Explanation - Class B IPv4 addresses have a default subnet mask of 255.255.0.0, meaning the first two octets define the network portion.
Correct answer is: 255.255.0.0
Q.2 Which of the following is a valid IPv6 address?
192.168.0.1
FE80::0202:B3FF:FE1E:8329
256.100.50.25
172.16.0.1
Explanation - IPv6 addresses are 128-bit hexadecimal addresses, represented in 8 groups of 4 hex digits separated by colons.
Correct answer is: FE80::0202:B3FF:FE1E:8329
Q.3 What is the maximum number of hosts in a /26 subnet?
64
62
32
30
Explanation - A /26 subnet has 6 bits for hosts (2^6=64). Excluding network and broadcast addresses, there are 62 usable host addresses.
Correct answer is: 62
Q.4 Which class of IP address provides the largest number of networks?
Class A
Class B
Class C
Class D
Explanation - Class C addresses have 21 bits for networks, providing more network options but fewer hosts per network.
Correct answer is: Class C
Q.5 What is the loopback IPv4 address?
127.0.0.1
192.168.1.1
0.0.0.0
255.255.255.255
Explanation - 127.0.0.1 is reserved as the loopback address to test network software without sending packets on the network.
Correct answer is: 127.0.0.1
Q.6 Which IPv4 address is reserved for private networks?
10.0.0.0
172.16.0.0
192.168.0.0
All of the above
Explanation - IPv4 reserves certain ranges (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) for private networks.
Correct answer is: All of the above
Q.7 What is the total number of IPv6 addresses available?
2^32
2^64
2^128
2^256
Explanation - IPv6 uses 128-bit addresses, providing 2^128 possible unique addresses.
Correct answer is: 2^128
Q.8 Which of the following represents a valid subnet in CIDR notation?
192.168.1.0/24
10.0.0.0/33
172.16.0.0/8/16
255.255.255.0/24
Explanation - CIDR notation expresses the network prefix as the number of bits in the subnet mask. /24 is valid.
Correct answer is: 192.168.1.0/24
Q.9 What is the purpose of subnetting?
Reduce network traffic
Improve security
Efficiently use IP addresses
All of the above
Explanation - Subnetting divides a network into smaller segments, reducing broadcast traffic, improving security, and optimizing IP usage.
Correct answer is: All of the above
Q.10 How many bits are used for the host portion in a /20 subnet?
12
20
8
24
Explanation - IPv4 addresses are 32 bits. /20 means 20 bits for network, leaving 12 bits for hosts.
Correct answer is: 12
Q.11 Which of the following is a multicast IPv4 address?
224.0.0.1
192.168.1.1
10.0.0.1
172.16.0.1
Explanation - IPv4 addresses from 224.0.0.0 to 239.255.255.255 are reserved for multicast traffic.
Correct answer is: 224.0.0.1
Q.12 In IPv6, which address type is used to communicate with all nodes on the local link?
Unicast
Multicast
Anycast
Link-local multicast
Explanation - IPv6 uses FF02::1 as the link-local multicast address for all nodes on a local link.
Correct answer is: Link-local multicast
Q.13 What is the broadcast address for the subnet 192.168.10.0/28?
192.168.10.15
192.168.10.14
192.168.10.16
192.168.10.0
Explanation - A /28 subnet has 16 addresses (2^4), from .0 to .15. The last address (.15) is the broadcast address.
Correct answer is: 192.168.10.15
Q.14 Which of the following is NOT a valid IPv4 address?
0.0.0.0
255.255.255.255
192.168.300.1
127.0.0.1
Explanation - Each octet of an IPv4 address must be between 0 and 255. 300 is invalid.
Correct answer is: 192.168.300.1
Q.15 What is the first usable IP address in the subnet 10.10.10.0/24?
10.10.10.0
10.10.10.1
10.10.10.254
10.10.10.255
Explanation - In a subnet, the first address is the network address, the next is the first usable host address.
Correct answer is: 10.10.10.1
Q.16 Which IPv6 address format allows omitting consecutive zero blocks?
Full notation
Compressed notation
Binary notation
Decimal notation
Explanation - IPv6 allows zero compression using :: to represent consecutive zero blocks.
Correct answer is: Compressed notation
Q.17 What is the prefix length for a subnet mask 255.255.255.128?
/24
/25
/26
/27
Explanation - 255.255.255.128 has 25 bits set to 1, giving a /25 prefix length.
Correct answer is: /25
Q.18 Which address is used to send a packet to any one of multiple hosts in IPv6?
Unicast
Anycast
Multicast
Broadcast
Explanation - IPv6 Anycast addresses allow delivery to the nearest host from a group of potential receivers.
Correct answer is: Anycast
Q.19 How many host addresses are available in a /30 subnet?
4
2
6
14
Explanation - /30 subnet provides 4 addresses, but 2 are reserved for network and broadcast, leaving 2 usable hosts.
Correct answer is: 2
Q.20 Which of the following is a valid loopback IPv6 address?
::1
FF00::1
2001::1
FE80::1
Explanation - ::1 is the IPv6 loopback address equivalent to IPv4 127.0.0.1.
Correct answer is: ::1
Q.21 What is the valid range of the first octet in a Class A IPv4 address?
0-127
128-191
192-223
224-239
Explanation - Class A IPv4 addresses have the first octet in the range 0-127.
Correct answer is: 0-127
Q.22 Which subnet mask corresponds to /22?
255.255.252.0
255.255.255.0
255.255.254.0
255.255.248.0
Explanation - /22 means 22 bits for network, leaving 10 bits for hosts, which corresponds to 255.255.252.0.
Correct answer is: 255.255.252.0
Q.23 Which IPv4 address class is used for multicast?
Class A
Class B
Class C
Class D
Explanation - Class D IPv4 addresses (224.0.0.0 to 239.255.255.255) are reserved for multicast groups.
Correct answer is: Class D
Q.24 What is the first address of the subnet 192.168.100.64/26?
192.168.100.0
192.168.100.64
192.168.100.65
192.168.100.127
Explanation - The subnet 192.168.100.64/26 has a range from .64 to .127. The first address is the network address, .64.
Correct answer is: 192.168.100.64