Yate is a next-generation telephony engine. While currently focused on Voice over Internet Protocol (VoIP) and PSTN, its power lies in its ability to be easily extended. It supports SIP, H.323, IAX, MGCP, Jingle, Jabber, E1, T1, analogic, robbed bit, ISDN PRI, BRI, and SS7. YateClient is an Instant Messenger and Voice application for Jabber/Jingle IM, SIP, H.323, and IAX VoIP protocols.
GkAuth is a call management system written for the GNU Gatekeeper project. It functions by connecting to the status port of the gatekeeper and collecting signals in its database. It provides Web based administration and user interface and stores its data in SQL tables. Key features include a Web-based management interface, run-time user administration (add/remove/modify user rights), prepaid/post paid/free billing, and call history.