What is CIDR ?
CIDR (Classless Inter-Domain Routing) is a method of representing IP networks that tells you how much of an IP address identifies the network and how much identifies the host (device). CIDR (Classless Inter-Domain Routing) is a method of representing IP networks that tells you how much of an IP address identifies the network and how much identifies the host (device). The format is: IP_Address/Prefix_Length For example: 192.168.1.0/24 192.168.1.0 = Network address /24 = The first 24 bits are the network portion. How CIDR works An IPv4 address has 32 bits , divided into four octets (8 bits each). Example: 192.168.1.10 Binary: 11000000.10101000.00000001.00001010 If the CIDR is /24 , it means: Network bits Host bits 11111111.11111111.11111111.00000000 ^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^ 24 bits 8 bits The first 24 bits identify the network, and the remaining 8 bits identify individual devices. CIDR and subnet mask Each CIDR prefix co...