Nokia NRS I Practice Test 2025 – Complete Exam Prep

To determine how many subnets can be created from the network 138.120.140.0/22 that can support 126 hosts each, we first analyze the requirements for subnetting.

A /22 subnet mask indicates that the first 22 bits are used for the network portion, leaving 10 bits for host addresses (since there are 32 bits in total for an IPv4 address). The total number of host addresses available in a /22 subnet can be calculated using the formula 2^n - 2, where n is the number of host bits and the subtraction accounts for the network and broadcast addresses.

In this case:

- n = 10 (from the /22 subnet mask)

- Total host addresses = 2^10 - 2 = 1024 - 2 = 1022 valid addresses.

Since each subnet must support 126 hosts, we need to find out how many subnets can be created that meet this criterion. Each subnet requires a certain number of bits to represent the hosts. To find the number of bits needed for at least 126 hosts, we calculate using the formula:

2^m - 2 ≥ 126

where m is the number of bits used for host addresses in each