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/**@name OpenH323 Libaray
This is a Open Source class library for the development of applications
that wish to use the H.323 protocol for multi-media communications over
packet based networks.
@memo A Class Libarary implementing the H.323 Protocol.
@version 1.7
@author Equivalence Pty. Ltd.
*/
//@{
/**@name Introduction
\begin{center}
{\Large{\bf OpenH323 Class Library}}
\end{center}
OpenH323
*/
/**@name Architecture
\begin{center}
{\Large{\bf OpenH323 Architecture}}
\end{center}
The fundamental object of the ownership hierarchy is of the H323Endpoint
class. An application would typically have one instance of a descendant of
this class. The application defined descendant would set up defaults for
various H323 parameters (timeouts etc), the most important of which is the
capability table which defines the codecs and channel types the application
is capable of handling.
Also created by the application in the H323Endpoint would be instances of one
or more descendants of the H323Listener class. There is a descendant of this
class for each protocol that is supported. For example H323ListenerIP would
be for Internet use. Each listener spawns a thread that monitors its protocol
and when a new incoming call is detected, creates an instance of a
H323Transport class descendent. As for the H323Listener class, there is a
descendent for each protocol supported, eg H323TransportIP.
When the first PDU arrives on a H323Transport using the Q.931 and H.225
protocols, there is a call reference that identifies the connection that has
been made. These connections are embodied by the H323Connection class, which
contains all of the state information for a connection between H323 endpoints.
The H323Endpoint instance keeps track of these active connections. If there
is no connection for the call reference number already, a new one is created
and H323 signalling negotiations begun.
An application would often have the system create an instance of a descendant
of the H323Connection class, rather than that class itself. This is so that
any of a large number of virtual methods may be overridden. These virtual
methods are "callback" functions by the library to allow the application to
either obtain information or modify the behaviour at various phases of the
protocol negotiations. For example, there is a callback for when an incoming
call is in progress and the application user should be "alerted". This is
highly application specific being anything from a simple audible beep to
displaying a pop up window with bells and whistles.
The H323Negotiator classes are used to maintain the state and functionality
of each command or variable defined by the H.245 protocol. Their main reason
for existence is actually to reduce the scope of the h225.h and h245.h files,
which define many hundreds of classes. A user of the H323Connection class
thus does not have to include all of these classes on every compilation unit.
During some of the H.245 negotiations, logical channels may be created, both
by the remote endpoint and by the local application. The H323Channel class
descendants represents this. A typical use of one of these classes is to open
a stream of encoded audio data. The H323Channel class would create a
H323Codec using the H323Capability that was passed during the protocol
negotiations.
*/
/**@name Using OpenH323
Detailed tutorials will be forthcoming.
@memo Brief examples.
*/
/**@name Class Reference
@memo Documentation on all classes.
*/
//@{
//@Include: include/h323.h
//@Include: include/h323ep.h
//@Include: include/h323con.h
//@Include: include/transports.h
//@Include: include/gkserver.h
//@Include: include/gkclient.h
//@Include: include/channels.h
//@Include: include/mediafmt.h
//@Include: include/h323caps.h
//@Include: include/h323t120.h
//@Include: include/h323t38.h
//@Include: include/codecs.h
//@Include: include/h263codec.h
//@Include: include/h261codec.h
//@Include: include/lid.h
//@Include: include/ixjlid.h
//@Include: include/vpblid.h
//@Include: include/rtp.h
//@Include: include/jitter.h
//@Include: include/h323rtp.h
//@Include: include/h323neg.h
//@Include: include/h323pdu.h
//@Include: include/h450pdu.h
//@Include: include/h225ras.h
//@Include: include/h235auth.h
//@Include: include/guid.h
//@Include: include/t120proto.h
//@Include: include/t38proto.h
//@Include: include/q931.h
//@Include: include/x224.h
//@Include: plugins/audio/GSM0610/inc/gsm.h
//@Include: plugins/audio/LPC_10/lpc10.h
//@Include: plugins/audio/Speex/libspeex/lpc.h
//@}
//@}
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