8 | | PJSIP libraries provide multi-level APIs to do SIP calls, presence, and instant messaging, as well as handling media and NAT traversal. Knowledge of SIP protocol details (such as the grammar, transaction, dialog, and whatnot) are not required (but it will help a lot!), however you should know how SIP works in general and particularly how to configure SIP clients to, e.g. register to a SIP provider, specify SIP URI to make call to, and so on, to use the module. |
| 8 | PJSIP libraries provide multi-level APIs to do SIP calls, presence, and instant messaging, as well as handling media and NAT traversal. PJSUA2 API is the highest API from PJSIP, on top of PJSUA-LIB API. PJSUA-LIB API itself is a library that unifies SIP, audio/video media, NAT traversal, and client media application best practices into a high level, integrated, and easy to use API. The next chapter will guide you on selecting which API level to use depending on your requirements. |
| 9 | |
| 10 | This documentation can be `viewed online <http://www.pjsip.org/docs/book-latest/html/index.html>`_, or alternatively you can `download the PDF format <http://www.pjsip.org/docs/book-latest/PJSUA2Doc.pdf>`_. |