In this paper we introduce Kurento Media Server: an open source WebRTC Media Server providing a toolbox of capabilities which include group communications, recording, routing, transcoding and mixing. Kurento supports a large number of media protocols such as WebRTC, plain RTP, RTSP or HTTP and bunch of codecs including VP8, VP9, H.264, H.263, OPUS, Speex, PCM or AMR. Kurento Media Server is based on a modular architecture, which makes it possible for developers to extend and customize its native capabilities with advanced media processing features such as computer vision, augmented reality or speech analysis. Kurento is ideal for WWW developers who find natural programming with its Java and JavaScript APIs following the traditional three tiered WWW development model.

WebRTC technologies are an opportunity for achieving a real convergence between WWW, desktop and mobile multimedia real-time communications services, which will contribute to defeating fragmentation and shall provide significant advantages to users and developers all around the world. Following this vision, in this paper we introduce Kurento, a media server technology based on open source software capable of demonstrating how this convergence could take place by combining a SIP/HTTP based signaling plane and a powerful media server infrastructure built on top of the GStreamer software stack. The presented technology is suitable for sending and delivering real-time multimedia through different protocols and formats and capable of providing advanced processing capabilities, which include media mixing, transcoding and filtering. Thanks to this, Kurento could push current WebRTC capabilities beyond plain peer-to-peer communication.