SIP Enum Support

ENUM is a protocol that uses DNS on internet to translate E.164 numbers (E.164=public enum directory of telephone numbers using ITU-T standard). Enum maps a telephone number to an e-mail address, website, VoIP address, etc. The 2020 IMG supports ENUM E2U+sip to resolve an ENUM telephone number into a SIP URI. The 2020 IMG enum is follows the procedures in the following RFC'S:

RFC 3764  - enumservice registration for Session Initiation Protocol (SIP) Addresses-of-Record

RFC 3761 - The E.164 to URI DDDS Application (ENUM)

RFC 3824 - Using E.164 numbers with SIP

RFC 3263 - Locating SIP Servers

RFC 3401 - Dynamic Delegation Discovery System (DDDS) - Part 1


Some of the benefits of enum on 2020 IMG are described below:

Follow the procedures below to configure ENUM service.


ENUM Diagram

Diagram below displays the 2020 IMG which accepts a E.164 telephone number. The 2020 IMG converts the number and adds to it as displayed below. The Database does a lookup and converts the query to E2U+SIP format ( and sends back to 2020 IMG where it is added to a SIP INVITE message. See diagram below.


Call Trace

Refer to Call Trace - ENUM link



The procedure below explains how to configure the 2020 IMG for a SIP enum query. Before configuring SIP ENUM, the 2020 IMG must have an initial configuration created on it. Follow the Basic Configurations procedure before proceeding onto configuring SIP enum feature.


Create a default Signaling Gateway Profile (SGP) and SIP signaling stack

  1. Right Click on the Profiles object and select New SIP SGP. If a profile other than the default SGP Profile will be used, modify the SIP Profile ID to something other than ID:0 to allow other fields in this object to be modified. In the SGP object enter a name in the SIP Profile Name field to identify this object. For more information on the SIP SGP page see SIP SGP.

  2. Right Click on 2020 IMG Name and select New Signaling. The Signaling Object is created to allow multiple signaling objects below it. No configuration is needed in this object. See Signaling for information on this object

  3. Right Click on Signaling Object just created and select New SIP. Select the SIP Gateway Profile just created from drop down menu in the Remote 2020 IMG’s SIP Profile. See screen capture below. Refer to SIP Signaling for more information on this page.

Create a SIP ENUM Server

  1. Right Click on 2020 IMG EMS and select New External Network Elements. This WebUI page is a container object of multiple external network elements and no configuration is needed. For more information refer to External Network Elements topic.
  2. Right Click on External Network Elements object and select New ENUM Server Set. Enter a name that identifies the ENUM Server Set being configured.
  3. Select the SIP SGP profile created above from the SIP Profile field. Refer to ENUM Server Set topic for more information.
  4. Right Click on ENUM Server Set and select New ENUM Server. Enter a name and IP address for the server the 2020 IMG will communicate with. Refer to ENUM Server for more information.

Configure SIP Channel Group

  1. Right Click on 2020 IMG EMS and select New Routing Configuration. See Routing Configuration for more information.

  2. Right Click on Routing Configuration and select New Channel Groups. This is a container object and no configuration is needed. Below the Channel Groups object, the Channel Group object can be created. Refer to Channel Groups topic for more information.

  3. Right Click on Channel Groups object and select New Channel Group. Enter a name to identify this channel group and change the Signaling Type to SIP using the drop down menu. Refer to SIP Channel Group for more information on configuring a SIP channel group.

Insert SIP External Network Element into SIP Channel Group

  1. Right Click on the SIP Channel group created and select New IP Network Element. Within the IP Network Element field, select from drop down menu, the ENUM Server created. See screen capture below.


Additional Information