SIP Thor is a Peer-to-Peer overlay that allows for load balancing, self-organization and geographical distribution of SIP infrastructure elements. SIP Thor allows for distribution of hardware resources in multiple datacenters and in different geographical locations. Using SIP Thor all relevant computing resources can be virtualized allowing for running the SIP services "in the cloud" with a high scalability/cost ratio. The infrastructure can scale deterministically to handle millions of end-points.
Real Time Communications Experts
OpenXCAP is an Open Source, easy extensible, fully featured XCAP server with TLS security and support for multiple realms. XCAP protocol allows a client to read, write, and modify application configuration data stored in XML format on a server.
OpenSIPS (Open SIP Server) is a mature Open Source implementation of a SIP server. OpenSIPS includes application-level functionalities. With a very flexible and customizable routing engine, OpenSIPS 'unifies voice, video, IM and presence services in a highly efficient way, thanks to its scalable (modular) design.
Adrian and Saul present a different view for the future of VoIP PBXs