Re: [MMUSIC] SCTP-SDP: Virtual Connection impact

Christer Holmberg <christer.holmberg@ericsson.com> Fri, 03 April 2015 14:37 UTC

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From: Christer Holmberg <christer.holmberg@ericsson.com>
To: Roman Shpount <roman@telurix.com>, Paul Kyzivat <pkyzivat@alum.mit.edu>
Thread-Topic: [MMUSIC] SCTP-SDP: Virtual Connection impact
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Date: Fri, 03 Apr 2015 14:37:27 +0000
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Subject: Re: [MMUSIC] SCTP-SDP: Virtual Connection impact
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Hi,
…

>I do agree a=connection:new is the better answer. One problem that I see with it, that it re-establishes all the protocols >running on the same m= line which support it. For instance if you have SCTP and DTLS used on the same m= line, both will >be reset when a=connection:new is specified. I am not sure how big of the problem this is for SCTP or other protocols and >if you would ever need to re-start SCTP without restarting DTLS or vice verse.

Assuming the DTLS connection is re-established due to change of device, the SCTP association would obviously also have to be re-established. 

(In fact, I believe re-establishing the SCTP association would more or less eliminate the risk of receiving packets associated with the old DTLS connection.)

Perhaps there could be cases where the SCTP association needs to be re-established, but not the DTLS connection. And, the SCTP stack itself could of course do that, without touching the DTLS connection, but I think we would simply say that the draft mechanism doesn't support explicit O/A negotiation of such action.

Regards,

Christer