SylkServer

h1. SylkServer WebRTC Managed Conference

h2. Design

h2. Features

h3. Ad-hoc conference

All participants are rendered in a matrix where each participants has the same size. The conference room has a fixed total bandwidth set by the server, which is divided between the participants, which means the more participants are in the room, the less bandwidth each participant will use keeping the bandwidth usage per conference room constant.

h3. Managed conference

The first participants becomes the manager. He can add/remove mute participants and also decide which one is the active speaker(s).

h2. Configuration

Sylkserver allows the maximum bitrate and video codec to be configured, globally or per room with the following settings in webrtcgateway.ini file:

<pre>

; Maximum video bitrate allowed per sender in a room in bits/s. This value is

; applied to any room that doesn't define its own. The value is any integer

; number between 64000 and 4194304. Default value is 2016000 (~2Mb/s).

; max_bitrate = 2016000

; The video codec to be used by all participants in a room. This value is

; applied to any room that doesn't define its own.

; Possible values are: h264, vp8 and vp9. Default is vp9.

; video_codec = vp9

</pre>

h2. Client support

h2. Measurements

This measurement was done on a Macbook Pro 15" with a 2.3GHz Intel Core I7 CPU, while having 7 participants in the room with each using 336Kb/s. The measurement shows the CPU usage in Firefox with the aforementioned conditions, for the specified video codecs and resolutions which are used by all participants:

<pre>

 * H264/VGA - 150% CPU

 * H264/HD  - 250% CPU

 * VP9/VGA  - 220% CPU

 * VP9/HD   - 350% CPU

</pre>

h2. Remaining tasks

 * sylkserver: control interface for moderator

 * janus: patch to request full frames when a paused video is resumed