Re: [AVTCORE] RTP/RTCP-mux: Attribute in answer if not included in offer?
Magnus Westerlund <magnus.westerlund@ericsson.com> Fri, 03 June 2016 08:59 UTC
Return-Path: <magnus.westerlund@ericsson.com>
X-Original-To: avt@ietfa.amsl.com
Delivered-To: avt@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id E59B612D1E2; Fri, 3 Jun 2016 01:59:13 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.221
X-Spam-Level:
X-Spam-Status: No, score=-4.221 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OG9ajz9wAWVe; Fri, 3 Jun 2016 01:59:11 -0700 (PDT)
Received: from sesbmg23.ericsson.net (sesbmg23.ericsson.net [193.180.251.37]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 373F512D551; Fri, 3 Jun 2016 01:59:11 -0700 (PDT)
X-AuditID: c1b4fb25-f79f26d00000327e-c5-575146dc806c
Received: from ESESSHC019.ericsson.se (Unknown_Domain [153.88.183.75]) by sesbmg23.ericsson.net (Symantec Mail Security) with SMTP id BC.80.12926.CD641575; Fri, 3 Jun 2016 10:59:09 +0200 (CEST)
Received: from [127.0.0.1] (153.88.183.153) by smtp.internal.ericsson.com (153.88.183.77) with Microsoft SMTP Server id 14.3.294.0; Fri, 3 Jun 2016 10:59:01 +0200
To: Christer Holmberg <christer.holmberg@ericsson.com>, Suhas Nandakumar <suhasietf@gmail.com>
References: <7594FB04B1934943A5C02806D1A2204B37FF17DE@ESESSMB209.ericsson.se> <CAMRcRGRK2s1MrgxsoHir6cF1n6WU1FTEFEAeTJ+VPzcmS9HSHw@mail.gmail.com> <D371CFE9.9672%christer.holmberg@ericsson.com>
From: Magnus Westerlund <magnus.westerlund@ericsson.com>
Message-ID: <37721757-37fe-df9d-9853-4bd59c0d16f4@ericsson.com>
Date: Fri, 03 Jun 2016 10:58:58 +0200
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0
MIME-Version: 1.0
In-Reply-To: <D371CFE9.9672%christer.holmberg@ericsson.com>
Content-Type: text/plain; charset="windows-1252"; format="flowed"
Content-Transfer-Encoding: 8bit
X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrDLMWRmVeSWpSXmKPExsUyM2K7t+5dt8Bwg6Mr+Sxe9qxkt1j+8gSj xdTlj1ksds7tYHZg8Zh2/z6bx85Zd9k9liz5yRTAHMVlk5Kak1mWWqRvl8CV0fP/CmPBc52K xQcXsjQwflHoYuTkkBAwkWjtuswIYYtJXLi3ng3EFhI4wigx9a1KFyMXkL2MUeLE10VACQ4O YYEQiQ0LskBMEYEEiTONXhAlRxkl3n+4xwTSyyzQyCix5YMXiM0mYCFx80cj2ExeAXuJrdd/ gdksAioS9xasB6sXFYiR2N41mR2iRlDi5MwnLCA2p4C1xJbFy9hBdjED9T7YWgYxXl6ieets ZogztSUamjpYJzAKzkLSPQuhYxaSjgWMzKsYRYtTi5Ny042M9VKLMpOLi/Pz9PJSSzYxAsP4 4JbfqjsYL79xPMQowMGoxMObsCYgXIg1say4MvcQowQHs5IIr7VtYLgQb0piZVVqUX58UWlO avEhRmkOFiVxXv+XiuFCAumJJanZqakFqUUwWSYOTqkGxhjNpMuMEw6uFX/06+SJjR+Ppt0I /MCbuL4vz9KoTEv189rXs5afV4xMTdBo2Vg/U1Bm7wX+HVqbD+VsMQgO/+P+ze/5okD+9qUf hb5dfRJ9qVhnfeHTuKN/AiUsd7WsZHltq345YdeOQ6kzXl6uSVPp2u92bb6M48JPeR2r9yYp fON/wfB92WolluKMREMt5qLiRADUliieXwIAAA==
Archived-At: <http://mailarchive.ietf.org/arch/msg/avt/UaJb4wI9llsSqdT1KLlI6oQ1ECo>
Cc: "Colin Perkins (csp@csperkins.org)" <csp@csperkins.org>, "mmusic@ietf.org" <mmusic@ietf.org>, "avt@ietf.org" <avt@ietf.org>
Subject: Re: [AVTCORE] RTP/RTCP-mux: Attribute in answer if not included in offer?
X-BeenThere: avt@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: Audio/Video Transport Core Maintenance <avt.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/avt>, <mailto:avt-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/avt/>
List-Post: <mailto:avt@ietf.org>
List-Help: <mailto:avt-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/avt>, <mailto:avt-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 03 Jun 2016 08:59:14 -0000
Den 2016-05-30 kl. 10:08, skrev Christer Holmberg: > Hi Suhas, > > I have the same understanding as you: the offerer indicates support of > RTP/RTCP-mux, and the answerer decides whether to use it or not. And, if > used, it will be used in BOTH directions – i.e. the usage of RTP/RTCP is > not per direction. > > Colin? Magnus? Yes, I do agree with your interpretations here. Both that it applies bi-directional after mutual agreement, and that if the answer would like to use it, it will have to do a re-invite with an offer including a=rtcp-mux attribute to see if the peer accepts that. /Magnus > > Regards, > > Christer > > From: Suhas Nandakumar <suhasietf@gmail.com <mailto:suhasietf@gmail.com>> > Date: Friday 27 May 2016 at 04:25 > To: Christer Holmberg <christer.holmberg@ericsson.com > <mailto:christer.holmberg@ericsson.com>> > Cc: "mmusic@ietf.org <mailto:mmusic@ietf.org>" <mmusic@ietf.org > <mailto:mmusic@ietf.org>>, "avt@ietf.org <mailto:avt@ietf.org>" > <avt@ietf.org <mailto:avt@ietf.org>>, Magnus Westerlund > <magnus.westerlund@ericsson.com > <mailto:magnus.westerlund@ericsson.com>>, Colin Perkins > <csp@csperkins.org <mailto:csp@csperkins.org>> > Subject: Re: [AVTCORE] RTP/RTCP-mux: Attribute in answer if not included > in offer? > > Going along O/A negotiation procedures, i would lean towards your former > conclusion that the offer needs to include the rtcp-mux ability. > If the offer doesn't include a=rtcp-mux and the answerer wants to mux , > then it needs a new O/A from the answerer's perspectives. > > > If we make a=rtcp-mux a declarative SDP it might solve the other use-case .. > > thanks > Suhas > > On Thu, May 26, 2016 at 1:01 PM, Christer Holmberg > <christer.holmberg@ericsson.com <mailto:christer.holmberg@ericsson.com>> > wrote: > > (Sorry for the cross-posting)____ > > __ __ > > Hi,____ > > __ __ > > There has been a discussion in 3GPP regarding RFC 5761 > (RTP/RTCP-mux).____ > > __ __ > > Section 5.1.1 says:____ > > __ __ > > 5.1.1. SDP Signalling____ > > __ __ > > When the Session Description Protocol (SDP) [8] is used to > negotiate____ > > RTP sessions following the offer/answer model [9], the > "a=rtcp-mux"____ > > attribute (see Section 8) indicates the desire to multiplex RTP > and____ > > RTCP onto a single port. The initial SDP offer MUST include this____ > > attribute at the media level to request multiplexing of RTP and > RTCP____ > > on a single port. For example:____ > > __ __ > > v=0____ > > o=csp 1153134164 1153134164 IN IP6 > 2001:DB8::211:24ff:fea3:7a2e____ > > s=-____ > > c=IN IP6 2001:DB8::211:24ff:fea3:7a2e____ > > t=1153134164 1153137764____ > > m=audio 49170 RTP/AVP 97____ > > a=rtpmap:97 iLBC/8000____ > > a=rtcp-mux____ > > __ __ > > This offer denotes a unicast voice-over-IP session using the > RTP/AVP____ > > profile with iLBC coding. The answerer is requested to send both > RTP____ > > and RTCP to port 49170 on IPv6 address > 2001:DB8::211:24ff:fea3:7a2e.____ > > __ __ > > If the answerer wishes to multiplex RTP and RTCP onto a single > port,____ > > it MUST include a media-level "a=rtcp-mux" attribute in the > answer.____ > > The RTP payload types used in the answer MUST conform to the > rules in____ > > Section 4.____ > > __ __ > > If the answer does not contain an "a=rtcp-mux" attribute, the > offerer____ > > MUST NOT multiplex RTP and RTCP packets on a single port. > Instead,____ > > it should send and receive RTCP on a port allocated according to > the____ > > usual port-selection rules (either the port pair, or a signalled > port____ > > if the "a=rtcp:" attribute [10] is also included). This will > occur____ > > when talking to a peer that does not understand the "a=rtcp-mux"____ > > attribute.____ > > __ __ > > Q: The question is whether it is allowed to include a=rtcp-mux in an > answer if the associated offer did NOT contain a=rtcp-mux.____ > > __ __ > > The second last paragraph in the text above does say that, if the > answer wishes to do RTP/RTCP-mux, it includes a=rtcp-mux in the > answer.____ > > __ __ > > BUT, in my view that is it based on the first paragraph, which > assumes a=rtcp-mux is also included in the offer.____ > > __ __ > > Or, am I wrong? Is it allowed to include a=rtcp-mux in the answer, > even if it’s not included in the offer? If so, how will the offerer > then indicate whether mux is used or not.____ > > __ __ > > Regards,____ > > __ __ > > Christer____ > > __ __ > > > _______________________________________________ > Audio/Video Transport Core Maintenance > avt@ietf.org <mailto:avt@ietf.org> > https://www.ietf.org/mailman/listinfo/avt > > -- Magnus Westerlund ---------------------------------------------------------------------- Services, Media and Network features, Ericsson Research EAB/TXM ---------------------------------------------------------------------- Ericsson AB | Phone +46 10 7148287 Färögatan 6 | Mobile +46 73 0949079 SE-164 80 Stockholm, Sweden | mailto: magnus.westerlund@ericsson.com ----------------------------------------------------------------------
- Re: [AVTCORE] [MMUSIC] RTP/RTCP-mux: Attribute in… Roman Shpount
- Re: [AVTCORE] [MMUSIC] RTP/RTCP-mux: Attribute in… Christer Holmberg
- Re: [AVTCORE] [MMUSIC] RTP/RTCP-mux: Attribute in… Roni Even
- [AVTCORE] RTP/RTCP-mux: Attribute in answer if no… Christer Holmberg
- Re: [AVTCORE] RTP/RTCP-mux: Attribute in answer i… Suhas Nandakumar
- Re: [AVTCORE] RTP/RTCP-mux: Attribute in answer i… Christer Holmberg
- Re: [AVTCORE] [MMUSIC] RTP/RTCP-mux: Attribute in… Roni Even
- Re: [AVTCORE] [MMUSIC] RTP/RTCP-mux: Attribute in… Christer Holmberg
- Re: [AVTCORE] RTP/RTCP-mux: Attribute in answer i… Magnus Westerlund
- Re: [AVTCORE] RTP/RTCP-mux: Attribute in answer i… Christer Holmberg