[AVT] RE: [BEHAVE] [Fwd: Last Call:draft-wing-behave-symmetric-rtprtcp(Common Local Transmit andReceive Ports (Symmetric RTP)) toInformational RFC]

Some NATs will close down NAT bindings after some number of seconds if there
is only outside->inside traffic and no inside->outside traffic on that same
5-tuple.  If you were to encounter such a NAT with the optimization you
describe below, the RTP traffic from the TURN server would stop after
awhile.  I suppose you could work around that NAT behavior, and still do
this optimization technique, if you were to send some sort of outgoing
traffic (inside->outside) to your own TURN server.

-d

> -----Original Message-----
> From: David Barrett [mailto:dbarrett@quinthar.com] 
> Sent: Tuesday, February 13, 2007 12:55 PM
> To: 'Dan Wing'; 'Magnus Westerlund'
> Cc: behave@ietf.org; 'IETF AVT WG'
> Subject: RE: [BEHAVE] [Fwd: Last 
> Call:draft-wing-behave-symmetric-rtprtcp(Common Local 
> Transmit andReceive Ports (Symmetric RTP)) toInformational RFC]
> 
> Though I think it's still a good recommendation, one thing I 
> found when
> working on iGlance was the case where two users were each 
> behind a different
> TURN relay server.
> 
> With symmetric RTP (if I understand correctly), for me to 
> send a packet to
> you I need to send it up to my TURN server, which forwards it 
> to your TURN
> server, which sends it to you.  Ideally I'd send it to your 
> TURN server
> direct, and cut out one relay.
> 
> The problem with this is it means our RTP isn't strictly 
> symmetric -- I
> receive from one place (my TURN server), but send to another 
> (your TURN
> server).
> 
> Am I misunderstanding how symmetric RTP works?  Perhaps this 
> is too minor a
> point to discuss here, however.
> 
> -david
> 
> > -----Original Message-----
> > From: Dan Wing [mailto:dwing@cisco.com]
> > Sent: Tuesday, February 13, 2007 12:44 PM
> > To: 'Magnus Westerlund'
> > Cc: behave@ietf.org; 'IETF AVT WG'
> > Subject: RE: [BEHAVE] [Fwd: Last Call:draft-wing-behave-symmetric-
> > rtprtcp(Common Local Transmit andReceive Ports (Symmetric RTP))
> > toInformational RFC]
> > 
> > Per Francois's suggestion, the following new text would be 
> placed at the
> > end
> > of section 3 of draft-wing-behave-symmetric-rtprtcp:
> > 
> >   "For these reasons it is RECOMMENDED that symmetric RTP and
> >    symmetric RTCP always be used for bi-directional RTP media
> >    streams."
> > 
> > -d
> > 
> > > -----Original Message-----
> > > From: Magnus Westerlund [mailto:magnus.westerlund@ericsson.com]
> > > Sent: Tuesday, February 13, 2007 12:17 PM
> > > To: Magnus Westerlund
> > > Cc: behave@ietf.org; IETF AVT WG
> > > Subject: Re: [BEHAVE] [Fwd: Last Call:
> > > draft-wing-behave-symmetric-rtprtcp(Common Local Transmit and
> > > Receive Ports (Symmetric RTP)) toInformational RFC]
> > >
> > > There has been raised a comment that this document should 
> contain a
> > > normative recommendation on using symmetric ports. However to
> > > make this
> > > happen the document would need to be a BCP. I am willing 
> to consider
> > > this but would like to have AVT and Behave WG 
> participant's view on
> > > doing this before progressing down that road and updating the
> > > IETF last
> > > call. So please provide comments by Tuesday 20th of Feb 
> on this issue.
> > >
> > > Best Regards
> > >
> > > Magnus
> > >
> > > Magnus Westerlund skrev:
> > > > Hi,
> > > >
> > > > This document has been raised before in both AVT and BEHAVE
> > > WG. I have
> > > > chosen to AD sponsor this document for publication as 
> informational
> > > > status because it seems to be of general interest. You have
> > > 4 weeks to
> > > > provide any comments on the document.
> > > >
> > > > Magnus Westerlund
> > > >
> > > > IETF Transport Area Director & TSVWG Chair
> > > >
> > > 
> ----------------------------------------------------------------------
> > > > Multimedia Technologies, Ericsson Research EAB/TVA/A
> > > >
> > > 
> ----------------------------------------------------------------------
> > > > Ericsson AB                | Phone +46 8 4048287
> > > > Torshamsgatan 23           | Fax   +46 8 7575550
> > > > S-164 80 Stockholm, Sweden | mailto: 
> magnus.westerlund@ericsson.com
> > > >
> > > 
> ----------------------------------------------------------------------
> > > >
> > > >
> > > --------------------------------------------------------------
> > > ----------
> > > >
> > > > Ämne:
> > > > Last Call: draft-wing-behave-symmetric-rtprtcp (Common
> > > Local Transmit
> > > > and Receive Ports (Symmetric RTP)) to Informational RFC
> > > > Från:
> > > > The IESG <iesg-secretary@ietf.org>
> > > > Datum:
> > > > Mon, 12 Feb 2007 15:44:51 -0500
> > > > Till:
> > > > IETF-Announce <ietf-announce@ietf.org>
> > > >
> > > > Till:
> > > > IETF-Announce <ietf-announce@ietf.org>
> > > >
> > > >
> > > > The IESG has received a request from an individual
> > > submitter to consider
> > > > the following document:
> > > >
> > > > - 'Common Local Transmit and Receive Ports (Symmetric RTP) '
> > > >    <draft-wing-behave-symmetric-rtprtcp-01.txt> as an
> > > Informational RFC
> > > >
> > > > The IESG plans to make a decision in the next few weeks,
> > > and solicits
> > > > final comments on this action.  Please send substantive
> > > comments to the
> > > > ietf@ietf.org mailing lists by 2007-03-12. Exceptionally,
> > > > comments may be sent to iesg@ietf.org instead. In either
> > > case, please
> > > > retain the beginning of the Subject line to allow 
> automated sorting.
> > > >
> > > > The file can be obtained via
> > > >
> > > http://www.ietf.org/internet-drafts/draft-wing-behave-symmetri
> > > c-rtprtcp-01.txt
> > > >
> > > >
> > > > IESG discussion can be tracked via
> > > >
> > > https://datatracker.ietf.org/public/pidtracker.cgi?command=vie
> > > w_id&dTag=13165&rfc_flag=0
> > > >
> > > >
> > > > _______________________________________________
> > > > IETF-Announce mailing list
> > > > IETF-Announce@ietf.org
> > > > https://www1.ietf.org/mailman/listinfo/ietf-announce
> > > >
> > > >
> > > >
> > > >
> > > --------------------------------------------------------------
> > > ----------
> > > >
> > > > _______________________________________________
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> > > > Behave@ietf.org
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> > >
> > >
> > > --
> > >
> > > Magnus Westerlund
> > >
> > > IETF Transport Area Director & TSVWG Chair
> > > 
> ----------------------------------------------------------------------
> > > Multimedia Technologies, Ericsson Research EAB/TVA/A
> > > 
> ----------------------------------------------------------------------
> > > Ericsson AB                | Phone +46 8 4048287
> > > Torshamsgatan 23           | Fax   +46 8 7575550
> > > S-164 80 Stockholm, Sweden | mailto: 
> magnus.westerlund@ericsson.com
> > > 
> ----------------------------------------------------------------------
> > >
> > > _______________________________________________
> > > Behave mailing list
> > > Behave@ietf.org
> > > https://www1.ietf.org/mailman/listinfo/behave
> > 
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> > Behave@ietf.org
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