Direct inward dialling numbers are virtual numbers that let you to route calls to your existing telephone lines. DIDs were established in order to be able to appoint certain employees a direct number, without requiring various physical phone lines. One DID number is able to route thousands of other calls to the proper extensions. With a DID number, a company can route calls to an unlimited amount of extensions.

Direct inward dialling was formed to reuse a limited number of phone lines to calls to different published phone numbers.Numbers help to route the calls to the existing business numbers. This process starts with a virtual landline number initiating call via cloud server and route calls to the customer number.Businesses can apply DID numbers to route incoming calls to the assigned DID number agents. The incoming calls can be automatically answered via IVR with a personalised greeting before addressing the customer query. A sub-type of DID numbers are also available in the form of Caller Line Identification. This feature enables in initiating a fixed business number for all outgoing calls and incoming calls. DID numbers in India are not available everywhere in India.