| source                               ^ source 
 | packets                              | packets
 v                                      | 
+-------------+                      +-------------+ 
|FEC          |             signaling|FEC          |
|             |             recovered|             |
|             |               symbols|             |
|             |                   <==|             |
+-------------+                      +-------------+
 | source  ^                            ^ source       
 | and/or  | sending                    | and/or
 | repair  | rate                       | repair
 | symbols | (or window)                | symbols
 v         |                            |
+-------------+                      +-------------+
|Transport    |               network|Transport    |
|(incl. CC)   |           information|             |
|             |network            <==|             |
|             |packets               |             |
+-------------+==>                   +-------------+

    SENDER                               RECEIVER