Janus is a WebRTC Gateway developed by Meetecho. Its sole purpose is to set up a WebRTC media communication with a browser, exchanging JSON messages with it, and relaying RTP/RTCP and messages between browsers and the server-side application logic they’re attached to. Specific features and applications are provided by server-side plugins. Browsers connect to these via the gateway to use the functionality they provide. Examples of such plugins can be implementations of applications like echo tests, conference bridges, media recorders, SIP gateways and the like. Test the demos here.
The concept allows deployment of a full-fledged WebRTC gateway on the cloud, or on a small nettop/box to handle a specific use case.