Mike's PBX Cookbook

Configure a Phantom DN

Phantom DN's are used to permanently call-forward one number to another, for example, to accommodate a service change, or to direct calls to a voicemail system.

Phantom DN's are used as an alternative to dummy (secondary) ACD queues, and typically route calls to Meridian Mail or Call Pilot dialable services (via the VSDN or SDN table). It is preferable (although not imperative) to use phantom DN's with Meridian Mail or Call Pilot because calls are forwarded with a "no answer" condition, as opposed to a "busy".

Phantom DN's emulate 500 sets, exist only in software, and require no hardware.
Virtual DN's are similar, exist only in software, but are used for IP sets and trunks.

Note:Phantom loops are for 500 type phones.
Virtual loops are for IP phones and trunks.

A phantom loop must be provisioned in the switch before you can configure phantom DN's.
To check if a phantom loop already exists, print the configuration record in LD22...

>LD 22
REQ  prt
TYPE  cequ

SUPL	000  004  008  012
        016  032  036  040
        048  P064 P068

A phantom loop is shown with the prefix P. Above, superloops 64 and 68 are phantom loops.

Configure a Phantom DN

Now that the phantom loop is provisioned on the switch, we can configure a phantom DN in Overlay 10. The important feature is DCFW (default call forward) which is only prompted for Virtual Terminals. This defines the "forward-to" number (max 31 digits), which may also be preceded by an access code (ACOD) if needed. An external call forward also requires CLS CFXA, and the appropriate NCOS level. Precede with an X to remove the DCFW.

LD 10

Prompt Response Description
REQ NEW Add new data
TYPE 500 Type of set
TN l s c u Terminal number, where l is the phantom loop, s is the shelf, c is the card, and u is the unit.
(for Option 11C, the TN is c u only - and different to the phantom loop number)
CDEN xx Defaults to 4D
DES xxxxxx Designator
CUST xx Customer number, usually 0
DN yyyy The dummy DN number, must be a single appearance.
Later, this DN will access a Voice Messaging or Multimedia Messaging service.
CLS UNR Unrestricted - Phantom DN's can not originate calls, so this is secure
FTR DCFW xx yyyy DCFW = Default Call Forward.
xx = digit length (even); yyyy = the CDN to which this DN forwards.
Set this to the Voice Messaging or Multimedia Messaging (for FAX) CDN queue.
  <enter> Accept defaults for the rest of the data block.

To add another DN, repeat these steps.
Exit Overlay 10 by entering: ****

Remember, Meridian Mail or Call Pilot will answer with something like "user does not subscribe to this servce" UNTIL an appropriate entry is made in the VSDN (Meridian Mail) or SDN (Call Pilot) table. However, if she does answer, you know the DCFW CDN is correct.

Call Forward External....

To call forward externally, for example: FTR DCFW 12 9123456 (where 9 is an access code), note the following points:

1. The Phantom DN will need CFTA (Call Forward by Call Type Allowed) and CFXA (Call Forward External Allowed) class of service options in LD 10. Both are default denied.

2. Check the Call Redirection Data Block (RDR_DATA) and confirm the following:

Note that the LD 10/11 CFTA is not the same as the LD 15 CFTA, and they must both be allowed.
Change CFO (default) to CFF if necessary, and make sure your Phantom DN has a suitable NCOS value.

- CFF means "Use the CLS/NCOS of the Forwarding TN to determine restriction in a CFW condition"
- CFO means "Use the CLS/NCOS of the Originating TN to determine restriction in a CFW condition"

Print RDR_DATA in LD 21, change it in LD 15.

3. For Trunk to Trunk connections to work, the following must be set to YES in NET_DATA:

Print NET_DATA in LD 21, change it in LD 15.

Note: Trunk to trunk will ONLY work over supervised trunks (LD 14: SUPN=YES, STYP BTS or other supervision type).

Second Level Forwarding

Second Level call forward (forwarding a forward) requires LD 10/11 class of service options: SFA (Second Level CFNA Allowed) and CNIA (Call Number Information Allowed). SFA won't work without CNIA, and both are default disabled.

Save changes!

When you have finished modifying the switch configuration, save your changes in Overlay 43. If you do not save your changes, all of your programming is lost when the switch is shut down. Load Overlay 43, and at the "." prompt, enter EDD to dump the data to disk.

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