+--------------+                +--------------+
          |              | SIP, XMPP, ... |              |
          |  Web Server  |<-------------->|  Web Server  |
          |              |                |              |
          +--------------+                +--------------+
                 ^                                ^
                 |                                |
           HTTP  |                                |  HTTP
                 |                                |
                 v                                v
                 JS API                       JS API
           +-----------+                     +-----------+
           |           |        Media        |           |
           |  Browser  |<------------------->|  Browser  |
           |           |                     |           |
           +-----------+                     +-----------+