Direct Inward Calling Number

The Direct Inward Calling Number object is a child of the Direct Inward Calling object. It defines how external callers can dial directly into individual terminals on the PBX, either by specifying a range of external directory numbers that map to these PBX terminals (Direct Inward Dialing, DID) or by specifying an external directory number that connects directly to the PBX so that the caller can specify an internal extension number (Direct Inward System Access, DISA).


The object's name is displayed in the EMS Tree View as either DID Range or DISA Number, depending on the value you specify for the Type field.

You can configure a limit on the number of simultaneous calls to a particular DISA Number or to numbers within a particular DID Range, to ensure that calls to a specific number or numbers do not take up all the available PBX Lines and prevent other calls from getting through. When the limit is reached, any further calls will be treated as though the PBX is busy. (These limits do not affect outgoing calls, so it is still possible for all lines to be busy even when the limits are in place, because the remaining lines are taken up with outgoing calls.) For example, you could use this feature as follows:

In order to use this feature, you will need to configure two or more DISA Numbers or DID Ranges, so that the essential lines are in one range and calls to the other range(s) are limited.


Parameter

Access

Description
Type Create Specifies the type of direct inward calling that this object defines. Values:
  • DID Range
    The object specifies a continuous range of external directory numbers that map to terminals on the PBX.
  • DISA number
    The object specifies a single external directory number that connects directly to the PBX.
Range size Create This field appears only if Type is set to DID Range. It specifies the number of directory numbers in the range.
(First) Directory number Create The meaning of this field depends on the Type field:
  • For DID Range, this field specifies the first 10-digit external directory number in the range.
  • For DISA number, this field specifies the 10-digit external directory number used to access the PBX.
Either type in the number (noting that if the Number status of the parent PBX object is Normal or Ported from, the directory number must be within an active Number Range), or click on the ellipsis symbol at the end of the field to select from the list of numbers not currently in use, as follows.
  • Select a Number Range.
  • For DID Range only: Select a boundary (10, 50, 100, 500, or 1000) to determine how the starting number in the range should be allocated, or select None if any starting number is acceptable.
  • Select Manual or Automatic block selection.
If you select Automatic, the NE allocates a number or a block of numbers that meets your requirements for range size and starting boundary. It also shows the continuous range of unallocated numbers around the selected block, to help you determine how the available numbers in the range will be fragmented by your selection. If necessary, you can go back and specify a different range size, number range and/or boundary. If you select Manual, the NE displays a list of all possible numbers or number blocks meeting your requirements that could be allocated, again showing the range of unallocated numbers around each number block. Select an appropriate number or block from the list, or go back and specify a different range size, number range and/or boundary if necessary.
Last Directory number Read only This field appears only if the Type field is set to DID Range; it specifies the last directory number in the range.
First code Change This field appears only if the Type field is set to DID Range; it specifies the code that will be pulsed to the PBX to identify the terminal corresponding to the first directory number in the range. Specify a numeric code of 2-10 digits (if the Call Agent signaling type of the parent PBX is Analog line / T1 CAS), or 2-25 digits (if it is ISDN PRI or SIP). If you do not specify a value, the EMS supplies a default value if the following criteria are met.
  • (First) Directory number is set.
  • Type is set to DID Range.
  • This field has not already been set (even by a previous default).
  • The parent PBX object has a Default number of DID digits value set.
The default value is the last digits of (First) Directory number, with a length equal to the value set in the parent PBX object's Default number of DID digits field.
Last code Read only This field appears only if the Type field is set to DID Range; it specifies the code that will be pulsed to the PBX to identify the terminal corresponding to the last directory number in the range.
Limit incoming calls Change Specifies whether to limit the number of simultaneous incoming calls to this number or range of numbers. Values:
  • True
    The number of simultaneous calls cannot exceed the value specified in the Maximum incoming calls field.
  • False (default)
    The number of simultaneous calls is not limited.
Maximum incoming calls Change This field appears only if Limit incoming calls is True. The maximum number of simultaneous incoming calls to this number or range of numbers. When the limit is reached, any further calls will be treated as though the PBX is busy.