HP-UX C SIP Stack Programmer's Guide (Novembery 2007)

SIP Stack 27
Enhanced Features
ENHANCED SIP
P
ARSER
The enhanced parser functionality provides more flexibility and allows message
“correction” by the application. This functionality is available both for sending
and receiving SIP messages.
MULTITHREADING SIP Stack can run in internally multithreaded mode (configurable). Your
application may either be single-threaded or multithreaded. SIP Stack uses locks
to ensure multithreading safety at the level of individual objects, such as call-
legs and transactions.
CONFIGURATION The SIP Stack configuration enables you to configure the following groups of
parameters:
 Memory allocation—you can predetermine the resources your
application will require during the SIP Stack operation, such as
the number of calls, register-clients, transactions, messages,
and transport buffer size.
 Logging levels
 Network parameters
 Timer values
 Other
LOGGING The SIP Stack includes a logging module that produces textual output messages
for the purpose of debugging, monitoring and tracking the activity of the
SIP Stack.
The logger can be configured to work on different levels of detail. You can
select a global log level for the entire SIP Stack. You can also assign different
log levels to the subcomponents of the SIP Stack, such as Call-leg layer,
Transaction layer, Message layer, transport and parser.
MEMORY
REQUIREMENTS
The SIP Stack is an optimized implementation of the SIP specification with
emphasis on minimal memory usage during run-time. The SIP Stack can be
fine-tuned for embedded systems and systems with low resources. The SIP
Stack has the following characteristics:
 Small code footprint
 Low per-call memory consumption
 Minimal call-stack requirements
 Emphasis on ROM usage (over RAM)
 No dynamic memory allocations
 Efficient internal resource management