Presence and IntComm WG

[Jon Zeeff <>]

> Date: Thu, 23 Oct 2003 09:33:20 -0400
> To: Ben Teitelbaum <>, , VoIP Working 
> Group <>
> From: Jon Zeeff 
> <>
> Subject: Re: Real and Non-Real Time Traffic (was [WG-PIC:352] Re: FMM demo 
> notes)
>
> > For now,
> > outside of pathological environments where hundreds of people are
> > sharing the ether, real-time applications with adaptive, loss-tolerant
> > codecs work well.
>
> Ether/ethernet - medium doesn't matter.
> Such environments are very common and shouldn't be ignored.  There are places
> that run with substantial packet loss all the time.  And they can't afford 
> more bandwidth.
>
> There are many more places that artificially constrict the pipes (eg, 10 
> mbit ethernet or even 128k) to/from their users as a primitive attempt to 
> reduce packet loss elsewhere.
>
> "The VoIP call used an ITU-T G.711 codec, plus proprietary FEC encoding, 
> plus RTP/UDP/IP framing."
>
>  "proprietary" in the above quote bothers me.  Given that packet loss is 
> a normal occurrence at
> some point in an Internet connection, effective FEC should be standard.
>
> > What worries me in the Internet2 environment are the non-adaptive
> > video applications we are seeing that are not at all "small".
>
> Agreed.  Same problem as voip but at data rates that are more likely to 
> cause problems.
>
> My concern is that non adaptive apps will start to use excessive FEC 
> (because it works)
> and all other apps will suffer.

Jon Zeeff
1-734-276-0632 (voice)
3025 Boardwalk, Suite 200; Ann Arbor, MI 48108
Copyright 2003 Jon Zeeff

----------------------------------------------------------------wg-pic-+
For list utilities, archives, subscribe, unsubscribe, etc. please visit the
ListProc web interface at 

   http://archives.internet2.edu/

----------------------------------------------------------------wg-pic--