Technically support for this is in various unix flavors (osx) of the  
VM. I think.
You might need to set some TCP/IP options to exploit via the socket  
plugin prim interface
for setting options.

On the other hand I've not heard of anyone using it to confirm it works.
Can not speak for windows, no idea how XP would treat this or if  
support in the windows VM socket code.

In both cases you would need to cross check the source code.

On Jul 3, 2007, at 1:40 PM, Frank Shearar wrote:

> J J's referring to sending UDP to multicast addresses. Basically,  
> interested
> parties signal (say, through the Internet Group Management  
> Protocol, IGMP
> (RFC 2236)) that they want to receive data sent to a particular  
> multicast
> address (RFC 3171 defines the (PIv4) multicast address range as  
> 224.0.0.0 to
> 239.255.255.255. Likely you'd be interested in an address in the
> 224.0.0.0/24 block, which is for link local multicast.). Datagrams  
> sent to
> that multicast address are duplicated and sent to all the interested
> parties.
>
> http://en.wikipedia.org/wiki/IP_Multicast is a good starting point for
> multicast.
>
> One thing to bear in mind is that any routers between the sender/s and
> receiver/s must support multicast.
>
> frank

--
======================================================================== 
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John M. McIntosh <johnmci at smalltalkconsulting.com>
Corporate Smalltalk Consulting Ltd.  http://www.smalltalkconsulting.com
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