RE: multicast connection trials from a home machine - is it regular?

["David Gillett" <gillettdavid () fhda edu>]

> Normally multicast packages are not routed by default. I'm 
> not quite sure if any ISP supports it. If they do, you are lucky.
> Otherwise you may need to install and configure a multicast 
> router in your home scenario and  setup a tunnel to an 
> multicast endpoint.
>
> Jan Falkenreck

> Normally multicast packages are not routed by default. 

  I'm not sure that this is a true statement.  On LANs without
IGMP support, what seems to happen "by default" is that when a
station sends a multicast packet, it goes to the router, which
attempts to deliver it by broadcasting it to at least the subnet
it arrived from.
  (And this is why the multicast option in Symantec's Ghost tends
to max out the router and flood the entire subnet....)

  It's not correct to assert that "network does not 'support'
multicast" equates to "multicast traffic is harmlessly dropped".

David Gillett


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