Configuring fcast

The Frame Broadcast Server application is fcast. It should be loaded in the PXS flash memory and defined as default application. See "Updating Software" in the LayGO PXS Installation Guide manual if you need to download fcast to the PXS and use the RedBoot default command, if necessary.

The Frame Broadcast Server is configured using a combination of a LayGO .cfg file stored in Flash memory and optional command line parameters set using the RedBoot options command. LayGO .cfg file contains all the configuration options related to the X.21 bis, Bisync, Monosync and HDLC LAPB protocols. See LayGO Configuration for details.

Command Line Options

The fcast server supports the following command line options:


  Do not autostart the server. The server will be started manually using
  the PXS control application.
  Default: Autostart the server


  Enable the use of HDLC LAPB.
  Default: disabled

[-f <cfg file>]

  LayGO cfg file.
  Default: fcast-dce.cfg

[-g <number of bytes to suppress>]

  Number of bytes to remove from the frame (1-10).
  Default: 0


  Enable passive listen mode on the synchronous connection.
  Default: use active connect mode

[-p <UDP port>]

  UDP port number to use for broadcast (1-65535).
  Default: 49173


  Enable receive from UDP mode.
  Default: send to UDP

[-s <UDP port>]

  UDP port number to use as the source port (1-65535).
  Default: system assigned

[-t <IP TTL>]

  IP TTL for multicast (1-255).
  Default: 1

[-u <IP address>]

  IP address to use for broadcast.

[-I <timeout>]

  Idle timeout in seconds (20-3600).  If no data has been received
  within the time limit, the link is reinitialized.
  Default: 0 (disabled)

[-L <timeout>]

  Link timeout in seconds (5-3600).  If the link fails, fcast waits for
  the link timeout to expire before attempting to reconnect.
  Default: 10

[-P <timeout>]

  Post timeout in minutes (5-1440).  When the post timeout expires, fcast
  posts link statistics to the logging server.
  Default: 60


  Enable line 1 as well as line 0.  Options following apply to line 1.
  Default: Disabled

IP Multicast Address Ranges

fcast will broadcast to any valid IP multicast address. The range is to The ranges which have been registered for use with the Internt Assigned Numbers Authority (IANA) are listed in Internet Multicast Addresses. However, for most private uses, registration is not required if the guidelines in RFC 2365 - Administratively Scoped IP Multicast are followed. This RFC gives guidelines for selecting addresses in the range of to The default address used by the fcast server,, is in the range defined by section 6.2:

6.2. The IPv4 Organization Local Scope -- is defined to be the IPv4 Organization Local
   Scope, and is the space from which an organization should
   allocate subranges when defining scopes for private use.