Presence_CallInfo Module

Ovidiu Sas

   <osas@voipembedded.com>

Edited by

Ovidiu Sas

   <osas@voipembedded.com>

   Copyright © 2010 VoIP Embedded, Inc.
   Revision History
   Revision $Revision: 7754 $ $Date: 2011-02-23 20:57:21 +0200
                              (Wed, 23 Feb 2011) $
     __________________________________________________________

   Table of Contents

   1. Admin Guide

        1.1. Overview
        1.2. Dependencies

              1.2.1. OpenSIPS Modules
              1.2.2. External Libraries or Applications

        1.3. Exported Parameters

              1.3.1. call_info_timeout_notification (int)
              1.3.2. line_seize_timeout_notification (int)

        1.4. Exported Functions

   List of Examples

   1.1. Set call_info_timeout_notification parameter
   1.2. Set line_seize_timeout_notification parameter

Chapter 1. Admin Guide

1.1. Overview

   The module enables the handling of "call-info" and "line-seize"
   events inside the presence module. It is used with the general
   event handling module: presence and it constructs and adds
   "Call-Info" headers to notification events. To send "call-info"
   notification to watchers, a third-party application must
   publish "call-info" events to the presence server.

   The module does not currently implement any authorization
   rules. It assumes that publish requests are only issued by a
   third-party application and subscribe requests only by
   subscriber to call-info and line-seize events. Authorization
   can thus be easily done by OpenSIPS configuration file before
   calling handle_publish() and handle_subscribe() functions.

   The module implements a simple check for the presence of
   Call-Info headers in received PUBLISH requests.

   To get better understanding on how the module works please take
   a look at the follwing figure:

   caller       proxy &   callee        watcher        publisher
alice@example  presence  bob@example  watcher@example
                 server
     |             |           |           |              |
     |             |<-----SUBSCRIBE bob----|              |
     |             |------200 OK---------->|              |
     |             |------NOTIFY---------->|              |
     |             |<-----200 OK-----------|              |
     |             |           |           |              |
     |--INV bob--->|           |           |              |
     |             |--INV bob->|           |              |
     |             |<-100------|           |              |
     |             |<-----PUBLISH(alerting)---------------|
     |             |------200 OK------------------------->|
     |             |------NOTIFY---------->|              |
     |             |<-----200 OK-----------|              |
     |             |           |           |              |
     |             |<-180 ring-|           |              |
     |<--180 ring--|           |           |              |
     |             |           |           |              |
     |             |           |           |              |
     |             |<-200 OK---|           |              |
     |<--200 OK----|           |           |              |
     |             |<-----PUBLISH(active)-----------------|
     |             |------200 OK------------------------->|
     |             |------NOTIFY---------->|              |
     |             |<-----200 OK-----------|              |
     |             |           |           |              |


     * The watcher subscribes the "Event: dialog" of Bob.
     * Alice calls Bob.
     * The publisher is publishing the "alerting" state for Bob.
     * PUBLISH is received and handled by presence module.
       Presence module updates the "presentity". Presence module
       checks for active watchers of the presentity. The active
       watcher is notified via a NOTIFY SIP request.
     * Bob answers the call.
     * The publisher is publishing the "active" state for Bob.
     * PUBLISH is received and handled by presence module.
       Presence module updates the "presentity". Presence module
       checks for active watchers of the presentity. The active
       watcher is notified via a NOTIFY SIP request.

1.2. Dependencies

1.2.1. OpenSIPS Modules

   The following modules must be loaded before this module:
     * presence.

1.2.2. External Libraries or Applications

   None.

1.3. Exported Parameters

1.3.1. call_info_timeout_notification (int)

   Enables or disables call_info event timeout notifications.

   Default value is “1” (enabled).

   Example 1.1. Set call_info_timeout_notification parameter
...
modparam("presence_callinfo", "call_info_timeout_notification", 0)
...

1.3.2. line_seize_timeout_notification (int)

   Enables or disables line_seize event timeout notifications.

   Default value is “0” (disabled).

   Example 1.2. Set line_seize_timeout_notification parameter
...
modparam("presence_callinfo", "line_seize_timeout_notification", 1)
...

1.4. Exported Functions

   None to be used in configuration file.