A method including: establishing connections, at a server, to at least two client devices using a call control protocol, the call control protocol negotiating video formats and connection information for sending and receiving media streams; receiving information from a first client at the server, the information comprising meta-data describing different media streams the first client is configured to transmit; transmitting the information received from the first client to the at least one other client; receiving a subscribe message from the at least one other client at the server, subscribing to at least one available media stream from the first client; in response to receiving at least one subscribe message from the at least one other client, transmitting, by the server, a message instructing the first client to start transmitting media streams subscribed to by the at least one other client; receiving, by the server, the media streams subscribed to by the at least one other client from the first client; and transmitting, by the server, the media streams subscribed to by the at least one other client to the at least one other client.