DISA (Direct Inward System Access) is used to allow people from the outside world to call into your PBX and then be able to dial out of the PBX so it appears that their call is coming from the office which can be handy when traveling. You can set a destination in an IVR that points to the DISA or set a DID. Make sure you password protect this to keep people from dialing in and using your PBX to make calls out.

Every effort should be made to hide this from the public and secure it. Leaving this exposed could lead to toll fraud and high phone bills.

To create a DISA, perform the following steps:

  1. Open the UCX Web-based Configuration Utility
  2. From the PBX tab, select PBX Configuration
  3. From the left side column, under Remote Access heading, select DISA
  4. Enter an appropriate DISA name
  5. Enter one or more PIN codes separated by commas, the user will be prompted to enter one of the PIN codes as the password
  6. Press the Submit Changes button

The description for all the fields on this page are listed below.

Field Description
DISA name A name to identify the DISA
PIN User will be prompted to enter this number as their password. Use a comma to separate multiple entries.
Response Timeout The maximum amount of time to wait (in seconds) before hanging up if the user has dialed an incomplete or invalid number. Default is 10.
Digit Timeout The maximum time (in seconds) permitted between digits when the user is entering an extension number. The default is 5.
Require Confirmation Require confirmation before prompting for password. Used when your PSTN connection appears to answer a call immediately.
Caller ID (Optional) When using this DISA, set the Caller ID to this value. Format is "User name" <5551234>
Context (For Experts Only) Set the context that calls will orginate from. Default value is from-internal. Do not change this value unless you know what you are doing.
Allow Hangup Allow the current call to be disconnected and dial tone presented for a new call by pressing the Disconnect feature code ** while in a call.
Caller ID Override Keep the Caller ID presented or override it. Default is Enable.


The following example uses a IVR to route calls to the DISA.

  • From an external phone, dial the number that will be routed to the IVR
  • From the IVR menu, enter 9 for DISA (using example below)
  • The user will be promted to enter a password (enter one of the PIN codes)
  • Dial tone will be presented to the user
  • User can now make calls as if they are calling from an internal extension