Direct inward dialing or primarily abbreviated as DID is an excellent feature provided by telecos to be used for convenience with private branch exchange or PBX communication systems. The purpose of inventing DID was to make it possible to reuse a restricted number of physical phone lines to manage calls from different assigned numbers. In DID service the telecos provides them trunk lines (either one or, if needed, more than one) to the consumers which then further connects it to the users’ PBX and assigns a number of telephone numbers to the same line (or group of lines) and sends forward all calls to such numbers by means of the trunk line. Since calls are connected to the Private Branch Exchange, the dialed destination number – or DNIS – is pulsed on, usually a part of the number mostly the last four numbers. The PBX in turn, uses these DID digits to directly switch the incoming call to the intended telephone extension within the organization’s premises, without having the need of a tele-operator to manage it. The service enables directing incoming calls, which are then routed to each extension, alongside maintaining barely a restricted number of users’ lines to gratify communication needs of all the customers simultaneously.
Direct inward dialing has enabled companies to keep separate phones and phone numbers without extending the number of phone lines. Previously, a PBX system required an operator to manually route the phone calls to desired extensions. But, with the advent of Voice over Internet Protocol or VOIP service, this has become a much convenient method than it was before. Now, with a Voip phone system we can easily route the calls to achieve the very same goal. Nevertheless, Voip offers better and faster technology for DID. This is how to converge Voip and DID:
DID – Direct Inward Dialing is rally a big feature offered by telephone companies in Europe for use with their customers’ PABX system, and the telephone company (telco) allocating a wide range of numbers to single or multiple phone lines.
I think the whole story has been depicted in an extremely technical way. The main thing is that local telephone exchange or in house exchange (for one company) can be better managed through voip phone technology. if anyone wants to upgrade his local exchange and shift on voip, he can use the method given above.
Let me know if i made the world easy for nontechnical people.
There are very few technicians available for this job throughout the world. Technology may be low cost but manpower is quite costly. However, the good thing is that this cost is a onetime cost. My question is there are countries, which do not allow voip calls. Can we use this system in those countries.
What a technolgy it is! I used to pay bulky bills on landlines each month. Now I just consume that is too low.