Learning OpenStack Networking - Third Edition

Working with IPv4 addresses

A few examples of IPv4 addresses and subnets described using CIDR notation are as follows:

• 192.168.100.50/24 represents the IP address 192.168.100.50, its associated routing prefix 192.168.100.0, and the subnet mask 255.255.255.0 (that is, 24 "1" bits). There are 256 total addresses in a /24, with 254 addresses available for use.
• 172.16.1.200/23 represents the IP address 172.16.0.200, its associated routing prefix 172.16.0.0, and the subnet mask 255.255.254.0 (that is, 23 "1" bits). There are 512 total addresses in a /23, with 510 addresses available for use.
• 10.0.10.4/22 represents the IP address 10.0.10.4, its associated routing prefix 10.0.8.0, and the subnet mask 255.255.252.0 (that is, 22 "1" bits). There ...