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
  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

Notes:

  Conforms to Pro-MPEG COP3 Forward Error Correction (FEC). This defines
  a method for sending two FEC RTP streams in addition to a source RTP
  stream enabling a receiver to reconstruct missing packets in the source
  stream.

  COP3 FEC requires two parameters, L and D. L affects the maximum burst
  packet loss that can be recovered. D defines latency involved in burst
  recovery. COP3 defines that L should be greater than or equal to 4 and
  less than or equal to 20. Likewise, D should be greater than or equal
  to 4 and less than or equal to 20. The product of L and D should be less
  than or equal to 100.

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

Products Supporting Command:

Created By: Adtec Digital Inc