GSMLIB is a library to access GSM mobile phones through GSM modems. Features include: modification of phonebooks stored in the mobile phone or on the SIM card, reading and writing of SMS messages stored in the mobile phone, sending and reception of SMS messages. Additionally, some simple command line programs are provided to use these features.
oRTP is a library implementing the Real-time Transport Protocol (RFC3550), written in C. It is easy to use and provides a packet scheduler for sending and receiving packets on time, adaptive jitter compensation, automatic sending of RTCP compound packets, and the RTCP parser API. It works with IPv6.
The SMSj library allows you to send SMSes (GSM) from the Java platform. It gives you full control over the SMS including the UDH field so you can create and send EMS messages, Nokia ringtones, and images. It provides a pluggable transport layer that allows it be used with a range of different SMS servers.
OrderlyCalls is a Java integration component for the popular Asterisk PBX. OrderlyCalls contains support for the Manager protocol as well as FastAGI. OrderlyCalls uses a Named Service approach to providing telephony services to your Java applications, and is configured with a user-extensible XML file. OrderlyCalls also offers native support for running inside J2EE Servlet Containers such as Tomcat, so you can easily add telephony functions to your Web applications.
Sofia-SIP is a SIP user agent library, compliant with the IETF RFC3261 specification. It can be used as a building block for SIP client software for uses such as VoIP, IM, and many other real-time and person-to-person communication services. The primary target platform is GNU/Linux. Sofia-SIP is based on a SIP stack developed at the Nokia Research Center.