What is DID - Direct Inward Dialing?
Direct Inward Dialing (DID) also known as Direct Dialing-in (DDI) in Europe, refers to an extension of an IP PBX (News - Alert) phone system that provides one or more trunk lines to PBX users and redirects all calls to the range of telephone numbers associated with the trunk.
DIDs eliminate the need for a receptionist or auto attendant to route calls to the appropriate phone lines. The single telephone line provided by the DID service allocates the range of phone numbers as desired by the company, not only saving the costs in having separate phone lines for each new number, but providing an efficient process to the management of all incoming calls as well.
Previously, in order for calls to be routed to the designated location, the last 3 or 4 digits of the number being dialed were entered before connecting the number. The PBX would then use these DID digits to switch the call to the right recipient.
Direct Inward Dialing services are typically utilized when a company’s PBX connection allows direct dialing to extensions within a PBX, using physical lines on a shared basis. DID services consist of identifying the called party by using DTMF or by digital means, before connecting each call.
DID has since become the new standard for VoIP and PBX platforms today. DID services were created in order to address the need for reusing the limited number of physical phone lines that can handle calls made to different lines. Providers of DID utilize phone companies to provide DID signaling which identifies the number they plan to connect with a business’s PBX phone system.
With DID, calls from designated phone numbers can be directly routed to an extension or ACD queue without the need for an auto attendant. In addition to calls, faxes can also be automatically routed to a specific extension without ever having to pass through an operator.
Using DID, a company can offer its customers individual phone numbers for each person or workstation within the company without requiring a physical line into the PBX for each connection. Compared to regular PBX services, DID also saves the cost of a switchboard operator since calls are able to transfer much faster and callers feel as though they are calling an individual employee rather than a company.
Many DID providers offer wholesale services to VoIP carriers, inbound call centers, CLEC’s and virtual carriers in order to expand their virtual presence in the IP communications market and allow wholesale carriers to offer the highest quality of DIDs to their customers as well.
DID is often combined with DOD (Direct Outward Dialing) which when coupled allows PBX extensions direct outbound calling capabilities with identification of their DID number.
Edited by Stefanie Mosca