FECPARAMS FEP FM

Description:

  Enable or disable the use of FEC for the encoder's multicast send and
  set the parameters for error correction.

Form:

  Command Handler: ECMD
  FECPARAMS|FEP|FM
  Argument List:

  Terse  Verbose     Description
  CHn            CHn      The FEP will be set for channel n, where n is a valid
                          channel number, starting at 0.
  If no CHANNEL is argued, the system will default to CH0.

  Terse  Verbose     Description
  0      OFF         Disable FEC
  1      ON          Enable FEC with current parameters
  2      MAXBURST    Enable FEC with L=20, D=4 (30% overhead, latency 100 packets)
  3      BURST       Enable FEC with L=14, D=7 (21% overhead, latency 112 packets)
  4      LOWLATENCY  Enable FEC with L=8,  D=8 (25% overhead, latency  64 packets)
  5      L <value>   Provide custom L value, default 14
  6      D <value>   Provide custom D value, default  7
  7      TOSBITS <value> Custom IP TOS value for FEC streams.

  TOSBITS Value List:
  Terse      Verbose      Description
   0         NORMAL       Default setting, normal service (0x00).
   2         MINMONY      Minimize monetary cost (0x02).
   4         MAXRELAY     Maximum reliability (0x04).
   8         MAXTHRUPUT   Maximize through put (0x08).
   16        MINDELAY     Minimize delay (0x10).

Response:

  MODIFY FECPARAMS RESPONSE
    Verbose- "OK\r\n" to acknowledge receipt of command, or
             "ERROR- [Description]\r\n" if error, ending command
    Terse-   "0\r\n" to acknowledge receipt of command, or
             "[NON-ZERO NUMERIC VALUE]\r\n" if error, ending command
    "\r\n" concludes modify responses (empty line)

  DISPLAY FECPARAMS RESPONSE
    Verbose- "OK\r\n" to acknowledge receipt of command, followed by
             "FEC= [OFF/ON/MAXBURST/BURST/LOWLATENCY]\r\n",
             "FEC L= [value]\r\n",
             "FEC D= [value]\r\n",
             "FEC TOSBITS= [NORMAL/MINMONY/MAXRELAY/MAXTHRUPUT/MINDELAY]\r\n", or
               "ERROR- [Description]\r\n" if error, ending command
    Terse-   "0\r\n" to acknowledge receipt of command, followed by
             "<state>, <l>, <d>, <tosbits>\r\n", or
             "[NON-ZERO NUMERIC VALUE]\r\n" if error, ending command
    "\r\n" concludes display responses (empty line)

Examples:

  Verbose command to retrieve current setting:
  *.ECMD FECPARAMS <enter>
     Response is: OK\r\n
                  FECPARAM= BURST\r\n
                  FEC L= 14\r\n
                  FEC D= 7\r\n

 Terse command to retrieve current setting:
  *.ECMD FM <enter>
     Response is: 0\r\n
                  0, 14,  7, 0\r\n

  Verbose command to change setting:
  *.ECMD FECPARAMS ON <enter>
     Response is: OK\r\n

  Terse command to change setting:
  *.ECMD FM 0 <enter>
     Response is: 0\r\n

  Verbose command to change setting:
  *.ECMD FECPARAMS L 20 <enter>
     Response is: OK\r\n

  Terse command to change setting:
  *.ECMD FM 5 20 <enter>
     Response is: 0\r\n

  Verbose command to change setting:
  *.ECMD FECPARAMS TOSBITS MINDELAY <enter>
     Response is: OK\r\n

  Terse command to change setting:
  *.ECMD FM 7 16 <enter>
     Response is: 0\r\n

  Verbose command to change setting for CH2:
  *.ECMD FECPARAMS CH2 L 16 <enter>
     Response is: OK\r\n

  Terse command to change setting for CH2:
  *.ECMD FM 2 7 16 <enter>
     Response is: 0\r\n

Notes:

  The Forward Error Correction technique implemented in this encoder
  conforms to the SMPTE 2022-1-2007 standard for the carriage of real-time
  Video/Audio content over IP networks. If the RTP FEC is enabled, the
  encoder will send two FEC streams to the receiving devices in order to
  reconstruct missing packets that occurred in the source stream. The FEC
  requires two parameters, L and D, affecting burst packet loss and
  latency, respectfully. The standard places three restrictions on these
  parameters; L is greater than or equal to 4 and less than or equal to
  20, D is greater than or equal to 4 and less than or equal to 20, and
  the product of L and D is less than or equal to 100.

  NOTE: RTP must be ON before FEC streams start.
  NOTE: FEC streams IP TTL matches the source stream.

• See RTP RTP R1
• See TTL TTL TL