Re: proposed charter 5 priority levels
"James M. Polk" <[email protected]> Mon, 30 Oct 2006 10:38:43 -0600
| Newsgroups | gmane.ietf.ieprep |
|---|---|
| Message-ID | <[email protected]> |
At 05:39 PM 9/27/2006 -0500, John Rosenberg wrote: >It's been mentioned that both RSVP and NSIS can carry both SIp priority >and DSCP. > >For the uninitiated (e.g. me!) would the use of either of these protocols >be used in a scenario where: > >1) an endpoint sent an INVITE to a call controller withtout RPH, but with >"dialed digits" that request a DSN precedence level (e.g. Flash); > >2) the call controller validated that the requested precedence level is >authorized; > >3) and the call controller then needs to inform the endpoint what specific >DSCP value (e.g. 41) to put in the bearer packets that the EP generates, >which value is based on a provisioned mapping resident in the call >controller between dsn precedence levels and DSCP values. John see http://www.ietf.org/internet-drafts/draft-polk-mmusic-dscp-attribute-00.txt Anyone wanting to make comments, please do so on the MMUSIC list to show those chairs there is interest in this ID. >Thanks, > >John > > > >At 09:15 PM 9/26/2006, Curtis Villamizar wrote: > > > >In message <[email protected]> > >John Rosenberg writes: > >> > >> At 05:52 PM 9/26/2006, [email protected] wrote: > >> > >> >Date: Tue, 26 Sep 2006 12:56:15 -0400 > >> >From: Curtis Villamizar <[email protected]> > >> > >> >In message > >> <OFBAA95066.05652C8C-ON852571F5.004A9C8A-852571F5.004B6690@csc.com> > >> >Janet P Gunn writes: > >> >> > >> >> > >> >> As RFC 4412 makes perfectly clear, the RPH serves a dual role of > >signalling > >> >> priority across an IP network (e.g. from an originating circuit > switched > >> >> access network to a terminating circuit switched access network) as > >well as > >> >> signalling priority within the IP network. > >> >> > >> >> For each of the namespaces described in RFC 4412, the number of > priority > >> >> values (5 in most cases, 6 in one) is driven by the former role, > based on > >> >> the number of priority values in use, or being considered, in the > access > >> >> network priority scheme. > >> >> > >> >> The issue of how many priority levels to differentiate WITHIN the IP > >> >> network is an issue currently being addressed by vendors and > providers. > >> >> > >> >> Janet > >> > > >> > > >> >Janet, > >> > > >> >You are right, but you may be just focusing on SIP which is one peice > >> >of the puzzle. > >> > > >> >RFC 4412 does not make it perfectly clear whether we need 1 DSCP code > >> >point, EF, or 5 DSCP code points (IP Prec 0-4?) or 15 DSCP code > >> >points (the 4 AF classes plus one more AF class. Or is it some > >> >multiple of 6? This RFC doesn't even mention DSCP. > >> > > >> > >> Let me add my voice and suggest that we're really in need of some > mechanism > >> that allows the application (e.g. MLPP, ETS, whatever) to determine a > >> "priority level" for a session and indicate to the endpoint that it's > >> serving what DSCP value that the endpoint should use for its bearer > packets. > >> > >> It could be a header or parameter in some subset of SIP messages, it could > >> be an attribute in SDP, it could be something else entirely. I think the > >> whole question of how many and which DSCP values should be used for some > >> arbitrary application is a little premature if we don't have a way for the > >> application to get that value used. > >> > >> John Rosenberg > > > > > >The discussion just went full circle. We already have a SIP priority > >in RFC4412. Use of DSCP is only touched on in RFC4190. Both the SIP > >priority and DSCP value can be carried in microflow RSVP > >(draft-briscoe-tsvwg-cl-architecture-03.txt). > > > >Which DSCP value seems to be an open issue for now. Discussion seems > >to favor a new DSCP EF-like value for ETS. > > > >Curtis > > >_______________________________________________ >Ieprep mailing list >[email protected] >https://www1.ietf.org/mailman/listinfo/ieprep