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== GNU ZRTP 1.1.0 ==

GNU ZRTP 1.1.0 implements the basic ZRTP as specificied in the document
''draft-zimmermann-avt-zrtp-06x''. You may access this at this URL:
[http://zfoneproject.com/zrtp_ietf.html]

This version of GNU ZRTP does not support the additiona featur of ZRTP
such as Multi-stream mode, Pre-shared mode, PBX enrollement, and SAS
Signature.  However, to keep the external interface as stable as
possible I already implmented stubs for the additional features. Some
later versions may have these features implemented, depending if they
are required by the community.

The current version of GNU ZRTP is compatible and was tested to work
with the latest Zfone beta (dated April, 2nd) (see Zfone project
site).

=== Interface changes ==

The ''SymmetricZRTPSession'' implements some new methods to control
ZRTP and its new features. An application usually uses only a few
methods to setup GNU ZRTP. All others are optional and an application
may use them only if it requires a special feature (which are not yet
implemented :-) ).

The ''ZrtpUserCallback'' class was modified as well. From an
application's point of view

* The methods in ''ZrtpUserCallback'' are not pure virtual anymore
   but just virtual and have a default implementation, usually a
   simple return. An application may extend this class and overwrite
   only those methods it requires.

* Change of the constructor - remove the queue parameter thus we have
  a very simple standard constructor. This modifcation may requires a
  small change in the application or class that uses or extends
  ''ZrtpUserCallback''.

* The method showSAS has an additional parameter:

     showSAS(std::string sas, bool verified);

  the verified flag is set to true in SAS is verified, false if not verified.
  This allows a more flexible support to display the SAS even if SAS is
  verified. Formerly ZRTP did not call "showSAS()" if SAS was verified. Now
  ZRTP always calls showSAS and provides the verification information
  explicitly.

* The siganture of the following user callback methods was changed:

        showMessage(GnuZrtpCodes::MessageSeverity sev, int32_t subCode)

        zrtpNegotiationFailed(GnuZrtpCodes::MessageSeverity severity,
                                           int32_t subCode)

  The GNU ZRTP core and the ZRTP ccRTP extension do not contain
  message strings anymore. Both use codes to inform an application
  about events, problems or failure. The folder ''demo'' contains a
  small demo program that shows one way how to map the codes to
  strings. Delegating string handling and formating to the application
  simplifies internationalization etc.

Plaese note: some new callback methods and ''SymmetricZRTPSession''
methods are only stubs in the currect version. The real implementation
(filling the stubs with real code) will be done some time later (see
above about unsupported features).

=== Header files ===

The new version greatly reduces the number of header files installed
in the include directory. In the new version I decoupled the internal
header files and implementation from the external classes and
interfaces an application requires. Only six header files are
installed in GNU ZRTP's include directory (libzrtpcpp subdirectory in
the usual include paths)

== Demo program ==

The new folder ''demo'' contains a small demo program that shows
various ways how to use GNU ZRTP to setup secure RTP (SRTP) sessions
even without signaling protocols