Subject: Re: Multicast address selection

From: [email-masked]
Date: Tue, 7 Oct 1997 09:38:56 -0700 (PDT)

> I have a question about the selection of multicast address.
> 
> If/When anyone would like to initiate a multicast session 
> in internet or intranet (not Mbone), how does he select the 
> multicast address ?
> 
> Are there any drafts about multicast address selection ?

The portion of the multicast address space 239.0.0.0 - 239.255.255.255 
is defined as administratively-scoped by convention, and, you can
subdivide that address space "by hand", either in a Cisco router
and/or by using the mrouted "name" command in /etc/mrouted.conf, and,
by telling sdr about it in .sdr/sdr.tcl using the "add_admin" command.
I forget if/where this is documented, but, it does let you create
working automatic multicast address assignment for sdr-controlled
sessions within an "intranet" in the 239.x.x.x address space, which
is assumed to be administratively-scoped by convention.  Eventually, 
this method, which is not very dynamic and which requires a bit more 
than the usual amount of end-user involvement, will be replaced.  
But, for the moment, it works, and if that is what is being looked-for,
I suggest using it.

  Hugh LaMaster, M/S 258-5,     ASCII Email:  [email-masked]
  NASA Ames Research Center     Or:           [email-masked]
  Moffett Field, CA 94035-1000  No Junkmail:  USC 18 section 2701
  Phone:  415/604-1056          Disclaimer:   Unofficial, personal *opinion*.