How VoIP Handles Direct Inward Dialing (DID)
Concepts behind Direct Inward Dialing
The telecommunications architecture in a business is fundamentally different from that found in a residential home. This is due to the number of phone connections required in a restricted area. Of course, mobile phones don't have this problem but wired lines need to be very densely packed in order to accommodate the number of users. But there's a limit to this close packing and soon phone companies had a problem - how do users get their own lines with a limited number of wires? The solution was Direct Inward Dialing.
In the early days of DID, a caller would dial a generic company number which an operator would answer and then manually route them to the required person either specifying them by name or by an extension number. Over time, this functionality was automated and people still use systems where a company number is dialed and an extension is given afterwards. Nowadays, it's possible for each employee to have their own telephone number handled by an Internet PBX. The telecom company will send the last few digits of the number which has been dialed and the PBX will figure out whom the caller wishes to speak to and connect them.
Because of this, DID is invisible to the user and works just like they would expect a regular phone number to work.
How VoIP Handles it
As expected, VoIP has the ability to easily handle DID numbers for everyone in a business. This means that each employee can have their own phone number which in turn can be configured to ring a variety of phones which the employee will pick up depending on where they are at the moment and which device is accessible to them.
It's important to keep in mind that a VoIP provider will lease a range of numbers from the telco and assign it to people in your organization. Also, unlike regular phones which employ circuit switching technology, it's not necessary for every VoIP user to have their own dedicated phone line. The Internet reaches everyone with its scalable architecture and there's no worry about lines being packed in too closely.
Of course, setting up DID on your own PBX can be a pain and requires careful configuration. If you have a secure hosted business VoIP service however, your ITSP will be able to set it up for you. Switching to hosted VoIP systems is easy. Just give your VoIP provider a call and ask them how to go about it.