Summarization or route summarization is the process by which we can represent multiple routes using a single statement. This is often used for representing ranges of IPv4 addresses, as well as IPv6 addresses to a lesser extent.
For example, the following four /24 networks can be summarized using a single statement:
- 192.168.0.0 / 24 subnet mask 255.255.255.0
- 192.168.1.0 / 24 subnet mask 255.255.255.0
- 192.168.2.0 / 24 subnet mask 255.255.255.0
- 192.168.3.0 / 24 subnet mask 255.255.255.0
Summarized network: 192.168.0.0 /22 subnet mask 255.255.252.0
Summarization should not be confused with the process of Supernetting.