Mike's PBX Cookbook

UDP Dialing to CS1K


Unable to UDP (Uniform Dialing Plan) dial from IP Office. Phone states "Incompatible" on screen.
IP Office 8.1 registered to NRS 7.50 with CS1000 7.50


Placing calls from IP Office to CS1000 and BCM using UDP (Uniform Dialing Plan) location codes.
CDP (Coordinated Dialing Plan) four digit dialing to main site is successful.
UDP calling to the IP Office also is successful.


Dialing 223 1111 to reach extension 1111 at Site A from the IP Office fails.
Dialing 1111 (assuming is in CDP) from IP Office is successful.
Dialing 224 2222 from any site to reach user at IP Office is successful.

Problem Clarification:

CS1000 contains many sites and already has UDP dialing for reaching branch offices. When implementing IP Office, UDP dialing into the site is working, but when attempting to UDP dial from the IP Office, all calls are failing. When the calls fail, they receive a message on the phone that states "Incompatible" CDP calling to any DNs available in the Coordinated Dialing Plan are successful.


The issue is occurring due to IP Office not sending phone context information within the SIP INVITE.
When IP Office is sending INVITE request to CS1000, it is not presenting any information for phone context, causing the NRS (Network Routing Service) to treat the call as CDP. This can be viewed within a packet capture of SIP traffic as the call is being initiated.


To allow for UDP phone context information to be presented, a manual Short Code will need to be created to send phone context information.

Within IP Office Manager, access Short Codes and create a new code for the UDP location code to be access. For the short code, provide the following:

Code/Name: ###N; 

(Replace  ### with the location code for UDP dialing, the  N is used as a variable to allow for an undetermined number of digits to be dialed.)

Feature: Dial

Telephone Number: ###N";phone-context=udp@domain.com" 

(Replace  ### with location code for UDP dialing, the N is used to allow for any number of digits to be presented after the location code.  udp and  domain can be retrieved from NRS if not already known. If all DNs at location are the same length, replace  N with sufficient number of  x to remove wait time after last digit)

Line Group ID: (choose appropriate line group)

Locale: (can be left blank)

Force Account Code: unchecked

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