Use CallBack through a PBX (Private Branch Exchange)

There is four categories of PBX systems on the marked today:

1: DIRECT INWARD DIALING (DID)
The Direct Inward Dialing is somewhat similar to a single line. 
DID: An offer service by the telephone company in which a large group of telephone numbers are provided service via a small number of trunks to customer equipment. The central office can transmit the last three to seven digits of the dialed number. The call goes directly through to a specific phone (extension).
No programming is needed.

2: DISA / TWO STEP DIRECT INWARD DIALING
A DISA facility will allow external callers to dial directly into a particular extension. After the main number is dialed the external caller will get a second dial tone or a greeting like: "Thank you for calling Acme Inc. Please enter the extension of the person you wish to contact".
We will have to program the switch to send the DTMF tones for the specific extension.
 - Contact the Customer Service Center to set up the PBX extension.

3: AUTOMATED ATTENDANT
The automated attendant systems are similar to the DISA systems described above. It may be possible to enter an extension as soon as the call is answered by the PBX. Other systems may require that a language is selected before it is possible to enter the extension. You may even have to go through a several steps in a menu before a specific extension can be selected. It is actually possible to program the switch to make the selections in the menu and get through to the right phone!!!
The digits will be automatically dialed upon receiving a callback. A comma ( , ) will cause a three second pause. We can add one more commas or remove one comma as appropriate to add a pause in-between the digits. We can also place an A, B, C or D tone that can be generated by the switch to trigger some equipment.
We will have to program the switch to send the DTMF tones for the specific extension.
 - Contact the Customer Service Center to set up the PBX extension.

4: MANUALLY OPERATED SWITCHBOARD
This is the old fashioned or "personal" way. GlobalTel's switch supports "extension" or "room number" caller announcement. The hotel or PBX operator will hear, "Please transfer this call to Nancy Stone, room number 210" or "Please transfer this call to Chuck Poole in marketing, extension 152".
You will have to activate and program the Travel Function.

Not sure it will work with your phone system?
Contact GlobalTel's technicians, and we will help you set it up in a few minutes!