Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiation mechanism
Roman Shpount <roman@telurix.com> Thu, 22 September 2011 14:53 UTC
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Date: Thu, 22 Sep 2011 10:55:27 -0400
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From: Roman Shpount <roman@telurix.com>
To: Hadriel Kaplan <HKaplan@acmepacket.com>
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Cc: "<rtcweb@ietf.org>" <rtcweb@ietf.org>
Subject: Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiation mechanism
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If we are planning to support SIP, then standard way of dealing with glare actually works fairly well. We would probably not get as much glare even with SIP if we would not use re-INVITEs for keep alive messages (SIP session timers). If we do not plan to support SIP, all we need is an ability in the API to cancel an offer and leave glare resolution to signaling. In general glare is unavoidable, for instance in case were both parties in the call decide for some reason to switch the video on. _____________ Roman Shpount On Thu, Sep 22, 2011 at 10:40 AM, Hadriel Kaplan <HKaplan@acmepacket.com>wrote: > > On Sep 22, 2011, at 9:57 AM, Tim Panton wrote: > > > At the risk of showing my ignorance - why are we expecting glare to be a > problem? > > To my mind glare only happens when you have a locked resource e.g. a busy > line > > or number . Rtcweb does not contain either of those concepts, what's the > resource > > that is being competed for here ? > > The resource being competed for is SDP state/media info of the same > session. If both sides send a new SDP offer during the session at the same > time, one side has to win. > > One would think this would be ultra-rare, but in SIP it happens a lot in > some deployments. > > -hadriel > > _______________________________________________ > rtcweb mailing list > rtcweb@ietf.org > https://www.ietf.org/mailman/listinfo/rtcweb >
- Re: [rtcweb] Minimal SDP negotiation mechanism Olle E. Johansson
- [rtcweb] Minimal SDP negotiation mechanism Harald Alvestrand
- Re: [rtcweb] Minimal SDP negotiation mechanism Paul Kyzivat
- Re: [rtcweb] Minimal SDP negotiation mechanism Hadriel Kaplan
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Olle E. Johansson
- Re: [rtcweb] Minimal SDP negotiation mechanism Christer Holmberg
- Re: [rtcweb] Minimal SDP negotiation mechanism Iñaki Baz Castillo
- Re: [rtcweb] Minimal SDP negotiation mechanism Harald Alvestrand
- Re: [rtcweb] Minimal SDP negotiation mechanism Christer Holmberg
- Re: [rtcweb] Minimal SDP negotiation mechanism Christer Holmberg
- Re: [rtcweb] Minimal SDP negotiation mechanism Harald Alvestrand
- Re: [rtcweb] Minimal SDP negotiation mechanism Olle E. Johansson
- Re: [rtcweb] Minimal SDP negotiation mechanism Christer Holmberg
- Re: [rtcweb] Minimal SDP negotiation mechanism Iñaki Baz Castillo
- Re: [rtcweb] Minimal SDP negotiation mechanism Magnus Westerlund
- Re: [rtcweb] Minimal SDP negotiation mechanism Roman Shpount
- Re: [rtcweb] Minimal SDP negotiation mechanism Olle E. Johansson
- Re: [rtcweb] Minimal SDP negotiation mechanism Cullen Jennings
- [rtcweb] Forking & Early Media - Was Re: Minimal … Cullen Jennings
- Re: [rtcweb] Minimal SDP negotiation mechanism Cullen Jennings
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Cullen Jennings
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Olle E. Johansson
- Re: [rtcweb] Minimal SDP negotiation mechanism Hadriel Kaplan
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Dzonatas Sol
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Hadriel Kaplan
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Hadriel Kaplan
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Ravindran Parthasarathi
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Roman Shpount
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Olle E. Johansson
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Ravindran Parthasarathi
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Saúl Ibarra Corretgé
- Re: [rtcweb] Minimal SDP negotiation mechanism Harald Alvestrand
- Re: [rtcweb] Forking & Early Media - Proposal Randell Jesup
- Re: [rtcweb] Forking & Early Media - Proposal Olle E. Johansson
- Re: [rtcweb] Minimal SDP negotiation mechanism Magnus Westerlund
- Re: [rtcweb] Minimal SDP negotiation mechanism Harald Alvestrand
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Muthu Arul Mozhi Perumal (mperumal)
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Roman Shpount
- Re: [rtcweb] Forking & Early Media - Proposal Roman Shpount
- Re: [rtcweb] Forking & Early Media - Proposal Randell Jesup
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Hadriel Kaplan
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Cullen Jennings
- [rtcweb] SIP Glare - Re: Minimal SDP negotiation … Cullen Jennings
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Tim Panton
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Hadriel Kaplan
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Roman Shpount
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Roman Shpount
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Magnus Westerlund
- Re: [rtcweb] Forking & Early Media - Proposal Elwell, John
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Harald Alvestrand
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Iñaki Baz Castillo
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Cullen Jennings
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Dzonatas Sol
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Matthew Kaufman
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Christer Holmberg
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Iñaki Baz Castillo
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Christer Holmberg
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Cullen Jennings
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Iñaki Baz Castillo
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Cullen Jennings
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Matthew Kaufman
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Christer Holmberg
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Cullen Jennings
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Hadriel Kaplan
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Roman Shpount
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Randell Jesup
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Christer Holmberg
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Christer Holmberg
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Hadriel Kaplan
- Re: [rtcweb] SIP Glare - Re: Minimal SDP negotiat… Magnus Westerlund
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Harald Alvestrand
- Re: [rtcweb] Forking & Early Media - Was Re: Mini… Christer Holmberg