What is CIDR?

CIDR, short for Classless Inter-Domain Routing, is a replacement for the older Classful network addressing architecture that was in use since 1981. CIDR was introduced in 1993 to address the issue of IP address shortage.

The CIDR method divides the address space for Internet Protocol Version 4 (IPv4) into five address classes. Each class, coded in the first four bits of the address, defines either a different network size, i.e. number of hosts for unicast addresses (classes A, B, C), or a multicast network (class D). The fifth class (E) address range is reserved for future or experimental purposes. Now, IPv6 is fast replacing IPv4 allowing huge expansion for more users and devices on the internet. 


Maskbits in CIDR allow you to discover specific IP ranges within the network.

Example: /24 is the Maskbit for the Subnet, i.e. = Range of IPs from to


      CIDR Maskbit    

    Total IPs in Range    

    Number of Class C networks        














To discover devices using CIDR, go to Settings -> Network Discovery. Click on New Discovery in the right top corner and select the Subnets tab. Enter the Network IP and its corresponding Maskbit to discover the desired set of devices.

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