added sst_b2b documentation

git-svn-id: http://svn.berlios.de/svnroot/repos/sems/trunk@1823 8eb893ce-cfd4-0310-b710-fb5ebe64c474

doc/Applications.txt

@@ -134,17 +134,27 @@ Various applications
    interfaces as XMLRPC server. This is very useful to connect SEMS with
    other software, that e.g. trigger click2dial calls, create
    registrations at SIP registrar, do monitoring, etc.
+
+   callback application can save lots of mobile calls costs, it calls back
+   caller and then the caller can enter a number to be connected to:
      * [30]Module Documentation: callback application plugin
 
+   auth_b2b application is identity change: A B2BUA where on the B leg the
+   caller identity and authentication is different. Can be used for
+   example for authenting to gateways.
      * [31]Module Documentation: auth_b2b application plugin
 
+   sst_b2b is SIP Session Timer enabled B2BUA, for making sure calls are
+   ended properly and without overbilling, and for topology hiding.
+     * [32]Module Documentation: sst_b2b application plugin
+
 Other components
 
-     * [32]Module Documentation: diameter_client component plugin
+     * [33]Module Documentation: diameter_client component plugin
      __________________________________________________________________
 
 
-    Generated on Wed Mar 17 14:15:58 2010 for SEMS by  [33]doxygen 1.6.1
+    Generated on Mon Apr 26 00:13:02 2010 for SEMS by  [34]doxygen 1.6.1
 
 References
 
@@ -179,5 +189,6 @@ References
   29. file://localhost/home/stefan/devel/sems/trunk/doc/doxygen_doc/html/ModuleDoc_xmlrpc2di.html
   30. file://localhost/home/stefan/devel/sems/trunk/doc/doxygen_doc/html/ModuleDoc_callback.html
   31. file://localhost/home/stefan/devel/sems/trunk/doc/doxygen_doc/html/ModuleDoc_auth_b2b.html
-  32. file://localhost/home/stefan/devel/sems/trunk/doc/doxygen_doc/html/ModuleDoc_diameter_client.html
-  33. http://www.doxygen.org/index.html
+  32. file://localhost/home/stefan/devel/sems/trunk/doc/doxygen_doc/html/ModuleDoc_sst_b2b.html
+  33. file://localhost/home/stefan/devel/sems/trunk/doc/doxygen_doc/html/ModuleDoc_diameter_client.html
+  34. http://www.doxygen.org/index.html

doc/Readme.sst_b2b.txt

@@ -0,0 +1,47 @@
+SIP Session Timers (SST) enabled B2B application.
+
+This application can be routed through for achieving 
+two things: 
+
+  1. Forcing SIP Session Timers, which prevents 
+     overbilling for calls where BYE is missing,
+     for example in cases where media (RTP) path 
+     does not go through the system, but billing 
+     is still done.
+
+  2. Topology hiding; this application acts as 
+     B2BUA, so on the B leg, no routing info from 
+     the A leg can be seen.
+
+The incoming INVITE for a newly established call is 
+passed in signaling only B2B mode to the B leg, 
+which tries to send it to the request URI.
+
+SIP Session Timers are enabled on both legs. When the 
+timer expires, an empty INVITE is sent, and the resulting 
+SDP offer from body of the 200 is relayed into the other 
+leg, where it is sent out as INVITE with the offer. The 
+answer from B leg is relayed into A leg and sent as body
+in ACK message.
+
+SST expiration is configurable in config file.
+
+
+ A                  b2b                  B
+ |---INVITE / SDPa-->|                   |
+ |                   |---INVITE / SDPa-->|
+ |                   |                   |
+ |                   |<-- OK/SDPb--------|
+ |                   |--- ACK ---------->|
+ |<-- OK/SDPb--------|                   |
+ |--- ACK ---------->|                   |
+ |                   |                   |
+
+          ... SST timer expires :
+ |                   |                   |
+ |<-- INVITE --------|                   |
+ |- OK/SDPc (offer)->|                   |
+ |                   |---INVITE / SDPc-->|
+ |                   |<-- OK/SDPd (answ)-|
+ |<----ACK/SDPd------|----ACK----------->|
+

doc/src/doc_applications.h

@@ -131,10 +131,22 @@
  * This is very useful to connect SEMS with other software, that e.g. trigger click2dial
  * calls, create registrations at SIP registrar, do monitoring, etc.  
  *
+ * callback application can save lots of mobile calls costs, it calls back caller 
+ * and then the caller can enter a number to be connected to:
+ *
  *  <ul><li> \ref ModuleDoc_callback </li></ul>
  *
+ * auth_b2b application is identity change: A B2BUA where on the B leg the caller
+ * identity and authentication is different. Can be used for example for authenting
+ * to gateways.
+ *
  *  <ul><li> \ref ModuleDoc_auth_b2b </li></ul>
  *
+ * sst_b2b is SIP Session Timer enabled B2BUA, for making sure calls are ended 
+ * properly and without overbilling, and for topology hiding.
+ *
+ *  <ul><li> \ref ModuleDoc_sst_b2b </li></ul>
+ * 
  * \section morecomponents Other components
  *
  *  <ul><li> \ref ModuleDoc_diameter_client </li></ul>
@@ -302,6 +314,14 @@
  *  Back to \ref AppDoc, to \ref AppDocExample.
  */
 
+/*! \page ModuleDoc_sst_b2b Module Documentation: sst_b2b application plugin
+ *  \section Readme_sst_b2b Readme file
+ *  \verbinclude Readme.sst_b2b.txt
+ *  
+ *  \section Links
+ *  Back to \ref AppDoc, to \ref AppDocExample.
+ */
+
 /*! \page ModuleDoc_diameter_client Module Documentation: diameter_client component plugin
  *  \section Readme_diameter_client Readme file
  *  \verbinclude Readme.diameter_client.txt