Answer Assignment about about IP addresses and subnet mask

CNIT 242 Assignment
System Administration
Question that make you understand about IP addresses.
Answer the following Questions for the given IP address:

130.1.1.0/21


Q1) which class, how many bits for the hosts? (10 points)



The given address 130.1.1.0/21 belongs to class B because the Range of class B IP address is 128.0.0.0 to
191.255.255.255

The given address falls in this range.

Here total number of bits for host = 32-21 = 11

Q2) number of bits borrowed and what is the subnet mask? (15 points)



In class B, number of network bits is 16

Hence /21 means the number of network+subnet bits is 21

So the number of bits borrowed = 21-16 = 5

Subnet mask: 11111111 11111111 11111000 00000000

255.255.248.0

Q3) what is block size/ total hosts for subnet mask? (15 points)



Block size = 2^host bits

= 2^11

= 2048 hosts



Q4) how many subnets (or networks) does the given subnet mask provide? (15 points)



The number of subnet bits = 21-16 = 5

Therefore, the number of subnets = 2^subnet bits = 2^5 = 32