Subnetting Calculation

Choose IP Address in OUM network

Network ID:     192.158.1.0/24

Subnet Mask:   255.255.255.0

Class Type:       Class C

Faculty:             12

Step 1:

Assume that OUM has 12 faculties means 12 subnets are needed,

2^n >= subnet needed

n = subnet bits

n >= 4 subnet bits (borrow bits)

Hence, the subnet is 2^4= 16

Step 2:

From the subnetting table, we know:

• When the subnet is 16, then each subnet will have 16 total host IDs including network ID and broadcast ID.
• /28 is the new subnet mask

Step 3:

• The first network ID is the original network ID which is 192.158.1.0
• As the host ID is 16, we need to add 16 from the previous network ID to get the next network ID
• By minusing 1 from the next network address, we will get the broadcast address of the previous network address
• To get the range of usable host of a network ID, take the next address after the network ID until the address before the broadcast address

Step 4:

The 4th available address is needed. Assuming that the Network ID for IT Centre is the 5th subnet address which is 192.168.1.64, the address 192.168.1.68 was chosen. Hence, the address for OnlineLearning System's server is 192.168.1.68.