System Release 6.1 cPCI for Windows Release Guide — May 2006 35
Support for TCP and UDP transport protocols
The Global Call IP call control library can be configured to accept incoming messages
that use the TCP transport protocol rather than UDP. When TCP support is enabled,
the library can be configured for which transport protocol to use as the default for SIP
requests, and this default transport protocol can be overridden by the application on a
message-by-message basis. The library can also be configured for how to handle
transport failures for SIP requests that are sent using UDP.
Support for INFO method
Applications can send or receive INFO requests and responses to allow transport of
application-level, session-related control information after the setup of a SIP session
has begun.
Support for OPTIONS method
Applications can send or receive OPTIONS requests and responses to allow a SIP
User Agent to query the capabilities of another UA or proxy either within or outside of
a SIP dialog.
Support for SUBSCRIBE and NOTIFY methods
Applications can send or receive SUBSCRIBE and NOTIFY requests and responses
to support event notification between nodes outside of a SIP dialog. Unsubscribed
NOTIFY messages (commonly used for MWI) are supported as well as subscribed
NOTIFY messages.
Expanded registration capabilities
The Global Call library now allows applications to query the SIP registrar for current
bindings as well as adding, changing, and deleting the bindings. The maximum
number of registrations can be configured when starting each virtual board to allow
users to be registered with multiple registrars or registered using multiple transport
addresses.
Support for digest authentication
The Global Call library supports the SIP digest authentication mechanism, which
allows a remote endpoint to challenge and authenticate the identity of a User Agent
which has sent it a request. A new gc_SetAuthenticationInfo( ) API, which is
documented in the Global Call IP Technology Guide, has been added to support this
functionality.
Support for 3xx responses, including redirect server capabilities
Applications are notified of incoming 3xx (redirection) responses, and are capable of
sending 3xx responses to support redirect server functionality.
Expanded support for provisional (18x) responses
Applications can specify which provisional response to send when accepting an
incoming call request. Applications that receive a provisional response from the
remote endpoint can distinguish among the different possible codes and can also
retrieve the Status-Code and Reason-Phrase.
New Global Call Features for ISDN Technology
The Global Call API library provides the following new features that apply to ISDN
technology:
