Version 7.2  681  Mediant 1000B Gateway & E-SBC 
 
User's Manual   32. Configuring General SBC Settings 
32  Configuring General SBC Settings 
This section describes configuration of various SBC features. 
 
32.1  Interworking Dialog Information in SIP NOTIFY 
Messages 
You can enable the device to interwork dialog information (XML body) received in SIP 
NOTIFY messages from a remote (WAN) application server. The NOTIFY message is sent 
by application servers to notify a SIP client, subscribed to a service and located behind the 
device (LAN), of the status of another  SIP client in the LAN. For example, user B can 
subscribe to an application server for call pick-up service, whereby if user A's phone rings, 
the application server notifies user B. User B can then press a pre-configured key 
sequence to answer the call.  
The NOTIFY message contains the XML body with call identifiers (call-id and tags). 
However, as the application server is located in the external network WAN and the SIP 
clients behind the device, the call dialog information sent by the application server reflects 
only the dialog between the device and itself; not that of the involved SIP clients. This is 
due to, for example, the device's topology hiding (e.g., IP address) of its LAN elements. 
The device resolves this by replacing the call identifiers received from the application 
server with the correct call identifiers (e.g., user A and user B). Thus, users subscribed to 
the service can receive relevant NOTIFY messages from the device and use the service.  
Figure  32-1: Interworking NOTIFY XML Body for Application Server 
 
  To enable the feature: 
  Configure the 'SBC Dialog-Info Interworking' (EnableSBCDialogInfoInterworking) 
parameter to Enable.  
When the feature is disabled, the device forwards the NOTIFY message  as is, without 
modifying its XML body. 
Below is an example of an XML body where the call-id, tags, and URIs have been replaced 
by the device: 
<?xml version="1.0"?> 
<dialog-info xmlns="urn:ietf:params:xml:ns:dialog-info" 
version="10" state="partial" 
entity="sip:alice@example.com"> 
<dialog id="zxcvbnm3" call-id="67402270@10.132.10.150" 
local-tag="1c137249965"