All things related to multicast

[Bob Riddle <>]

look at the ConferenceXP stuff (www.conferencexp.net)   It has a 
software echo cancellation built in - you'll need the spare CPU cycles 
to run it, but you don't need to buy & struggle with a ASPI or Gentner.

p.s.  the source code is freely available.

Hugh LaMaster wrote:

> On Thu, 13 May 2004, Greg Shepherd wrote:
>
>  
>
> > Conferencing has been repeatedly miss-identified as an "ideal" multicast
> > application. It is not. And acutally, much of the baggage we have today
> > with ASM came from that miss-targeted application.
> >
> > Greg
> >
> > On Thu, 13 May 2004, Bill Owens wrote:
> >
> >    
> >
> > > On Thu, May 13, 2004 at 04:24:36PM -0400, Richard Mavrogeanes wrote:
> > >      
> > >
> > > > My two cents:
> > > >
> > > > Multicast is not used more often because:
> > > >
> > > > 1. The default condition of virtually all routers is to disable
> > > >        
>      multicast.
>  
>
> > > . . .
> > >
> > > All true, and I certainly know that multicast is not an easy thing to
> > >      
>    configure, manage and repair (or even understand!) but I'm intentionally
>    preaching the choir here. I wasn't asking why Joe Public doesn't use
>    multicast more often, I was asking why *we* don't use it more often.
>  
>
> > > My application, weekly recurring conference calls with a standing group
> > >      
>    of people, all at Internet2 sites, all of them advanced network users,
>    seems like an ideal place to use multicast a/v tools - and yet, we don't.
>    There must be dozens of similar conference calls every week; heck, 
>    Internet2 has their own conference system, and they wouldn't have bothered
>    if they
>    didn't use it a lot. Isn't there something wrong with that picture?
>
> Conferencing isn't the killer app, but, network folks would use it 
> if only required a little more effort.  That would at least keep
> the infrastructure working.
>
> Im my experience, the biggest impediment to doing conferencing is lack
> of echo cancellation in full-duplex mode.  "vat" was amazing for its day,
> but, it didn't do echo cancellation in software, and nobody had or has
> H/W echo cancellation in their cheap host microphone/speaker setups.
> People didn't like "use-mouse-button-to-talk, but, had to.  Now that most
> desktops are probably at 360-400MHz CPU or better (maybe 2.4 GHz),
> software echo cancellation might work.  A lot of offices have speakerphones,
> and conference rooms mostly have decent phone setups.  In other words, 
> "It's the audio."
>
>
> ==============================================================================
> Hugh LaMaster, M/S 233-21,   Mail:   /~\ The ASCII  
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>
>  

--
Bob Riddle 
()
    Technologist,Internet2
3025 Boardwalk, Suite 100         Ann Arbor, Michigan  48108
Business Phone: 734.913.4257      Fax Number:  734.913.4255

"Math illiteracy affects 7 out of every 5 people"