IPv4 reference

IPv4 /11 prefix

IPv4 /11 prefix corresponds to /11, with 2,097,152 total addresses and 2,097,150 usable hosts.

Example network details for 0.0.0.0/11

CIDR
0.0.0.0/11
Prefix
/11
Network address
0.0.0.0
Broadcast address
0.31.255.255
First usable address
0.0.0.1
Last usable address
0.31.255.254
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255
Total addresses
2,097,152
Usable hosts
2,097,150

Binary masks

Subnet: 11111111.11100000.00000000.00000000

Wildcard: 00000000.00011111.11111111.11111111

The first 11 bits identify the network. The remaining 21 bits identify addresses inside it.

First subdivision

Dividing this network into 4 equal blocks produces:

Continue working with /11

What this result means

A /11 IPv4 network contains 2,097,152 consecutive addresses. The network and broadcast addresses are reserved in traditional LAN use, leaving 2,097,150 usable host addresses.

Use the wildcard mask in access lists and routing policy where a device expects inverse mask bits. Always verify vendor syntax before applying generated values to production equipment.