Configuring xcast

The X.25 Broadcast Server application is xcast. 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 xcast to the PXS and use the RedBoot default command, if necessary.

The X.25 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, HDLC LAPB and X.25 protocols. See LayGO Configuration for details.

Command Line Options

The xcast 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

[-c <DTE address>]

  Calling DTE address xcast should use to identify itself in
  X.25 call request packets.
  Default: <none>

[-d <DTE address list>]

  A text file containing DTE addresses (one per line) to establish
  connections with using Switched Virtual Circuits.
  Default: <none>

[-f <cfg file>]

  LayGO cfg file.
  Default: xcast-dte.cfg

[-i <IP address>]

  IP address to use for broadcast.
  Default: <>

[-p <UDP port>]

  UDP port number to use for broadcast (1-65535).
  Default: 1919

[-t <IP TTL>]

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


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

IP Multicast Address Ranges

xcast 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 xcast 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.