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What is CIDR?
CIDR (Classless Inter-Domain Routing) is a method for allocating IP addresses and performing IP routing. It uses prefix length to represent the size of the network portion, replacing traditional A, B, C class network divisions.
Subnet Mask
Subnet mask is used to distinguish the network portion and host portion in an IP address. The shorter the prefix length, the larger the network and more hosts; the longer the prefix length, the smaller the network and fewer hosts.
Subnet Division
Subnet division is the process of dividing a large network into multiple smaller sub-networks, which can improve network security, reduce broadcast domains, and optimize network performance. Consider actual requirements when dividing subnets.
Private IP Addresses
Private IP addresses include: 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16. These addresses can only be used within internal networks and cannot be directly routed on the Internet.