How is a network ID assigned in a CIDR IP address?

In CIDR IP addressing, the first 'n' bits of an IP address are assigned to identify the network and the remaining bits are used to identify the host, where the value of 'n' may be between 1 to 31. The value of 'n' depends on the number of hosts in the network.

What is the difference between classful IP addressing and classless IP addressing?

The difference between classful IP addressing and classless IP addressing is in selecting the number of bits used for the network ID portion of an IP address. In classful IP addressing, the network ID portion can take only the predefined number of bits 8, 16, or 24. In classless addressing, any number of bits can be assigned to the network ID.

Which RFCs discuss about CIDR?

RFCs 1517, 1518, and 1519 discusses about CIDR.

What is CIDR?

Classless Inter Domain Routing (CIDR) is a method for assigning IP addresses without using the standard IP address classes like Class A, Class B or Class C. In CIDR, depending on the number of hosts present in a network, IP addresses are assigned.

What are the possible solutions to the limitations of IP addressing?

The possible solutions to the limitation of IPv4 addressing are:

1. IP version 6 (IPv6) or IP next generation (IPng). This is the latest version of IP. This solves a lot of problems in IPv4. This document doesn't discuss about IPv6.

2. Classless Inter Domain Routing (CIDR)