Answer to Question #296111 in Computer Networks for kitty ku

Question

a) What is CIDR ? Why do we use classless instead of classful in ip subnetting ?

b) Describe the differences between CIDR 200.23.16.0/23 and 200.23.16.0/24

Answer 1

a) Classless Inter-Domain Routing is a set of IP standards or method used to allocate IP addresses to networks and hosts in an interconnection of networks. We use classless in IP sub netting instead of classful because classless addressing enables more efficient allocation of IP addresses than classful addressing which is kind of restricted since it divides its address space into classes which are restricted. So classless addressing prevents running out of IP addresses that occurs in classful.

b) The differences between CIDR 200.23.16.0/23 and 200.23.16.0/24 is that the former sub-net will have $2^9$ i.e. that sub-net will have 510 usable addresses while the latter sub-net will have $2^8$ i.e. (256-2= 254) usable IP addresses.