What are DID numbers? Direct inward dialing numbers (DIDs) are virtual numbers that allow you to route calls to your existing telephone lines. DIDs were developed in order to be able to assign certain employees a direct number, without requiring multiple physical phone lines. One DID number is able to route and process thousands of simultaneous calls to the proper extensions. With a DID number, a company can route calls to an unlimited amount of extensions, while only having to maintain one DID number.
Direct inward dialing was created as a way to reuse a limited number of physical phone lines to calls to different published phone numbers. A company can use one DID to route all of their inbound calls.
What is required to have an active DID?
In order to have an active DID, all that is required is to have a working transfer line to which calls can be forwarded. Companies like CallFire and Onebox offer IVR technology to route calls to a user’s phone line. That line could be a land line, cellphone, or digital line.
How are DID numbers used with PBX systems?
In many cases, direct inward dialing is used in conjunction with a company’s private branch exchange (PBX) systems. The DID provider allocates one or more trunk lines to the customer’s PBX, allocates a range of telephone numbers to this line, and forwards all calls to such numbers via the trunk. When calls arrive at the PBX system, the dialed destination number is transmitted so that the PBX can route the call to the desired extension. As a consequence of this call forwarding, a company can offer individual phone numbers for each employee or work station without requiring a physical telephone line for each number.
What is the advantage of having a DID route your calls through a PBX system?
The benefit of having a DID is that any person can call the extension, or phone number, in order to connect to the recipient without having to go through a switchboard or operator and without the company having to purchase bulk phone lines.