How to work out what IP addresses are available on the network

IP Addresses you know: 192.168.1.11, 192.168.1.1
Subnet mask is known to be 255.255.255.224

First determine the subnet range by performing a logical and bitwise AND operation on the binary forms of the last octet and the corresponding octet from the IP Address

Binary form of the subnet 11100000
Binary form of the known IP 00001011
AND 00000000

Subnet Address 192.168.1.0

Now you need to determine the range of addresses on the subnet

Convert the subnet(ted octet) to binary 11100000
Change all the 1’s except the last to 0’s 00100000
Convert to decimal 32
Remove the subnet and broadcast addresses 30

The range of IP Addresses available are 192.168.0.1 -192.168.0.30

Remove the hosts already on the network

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