Subnetting Questions 7 | Find the subnet mask for nine subnets with maximum host

Subnetting Questions 7

You are working with a network that has the network ID 192.168.10.0 and requires nine subsets for your company and the maximum number of hosts. What subnet mask should you use?

Solution

Hence, the IP Address start from 192, it indicates it is a class C Address. By default, in class C 24 bits are reserved for the network and 8 bits are reserved for the host.

A/Q we need minimum 9 subnets with the maximum host. So, we have to borrow 4 bits from the last octet (2ⁿ = 2⁴ = 16 Subnets)

(11111111.11111111.11111111.11110000)

(2⁷ + 2⁶ + 2⁵ + 2⁴ + 2³ + 2² + 2¹ + 2⁰) . (2⁷ + 2⁶ + 2⁵ + 2⁴ + 2³ + 2² + 2¹ + 2⁰) . (2⁷ + 2⁶ + 2⁵ + 2⁴ + 2³ + 2² + 2¹ + 2⁰) . (2⁷ + 2⁶ + 2⁵ + 2⁴)

So the subnet mask is: 255.255.255.240