Private IPv4 address ranges

Range Subnet Mask Range of IPs 10.0.0.0/8 255.0.0.0 10.0.0.0 - 10.255.255.255 172.16.0.0/12 255.240.0.0 172.16.0.0 - 172.31.255.255 192.168.0.0/16 255.255.0.0 192.168.0.0 - 192.168.255.255

Mask/Widlcard Decimal and Binary

Subnet Mask Binary Rep WildCard Binary 255 1111 1111 0 0000 0000 254 1111 1110 1 1000 0000 252 1111 1100 3 1100 0000 248 1111 1000 7 1110 0000 240 1111 0000 15 1111 0000 224 1110 0000 31 1111 1000 192 1100 0000 63 1111 1100 128 1000 0000 127 1111 1110 0 0000 0000 255 1111 1111

VLSM is a process of dividing an IP space into the subnets of different sizes without wasting IP addresses. When we perform subnetting, all subnets have the same number of hosts, this is known as FLSM ( Fixed length subnet mask).

CIDR notation is a compact representation of an IP address and its associated routing prefix. The notation is constructed from an IP address, a slash ('/') character, and a decimal number. The number is the count of leading 1 bits in the routing mask, traditionally called the network mask.