The MPLS-OPS Archive[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index][Thread Index][Author Index][Subject Index] RE: MPLS Trafficdriven
Hi Barry, Yes it would make sense. But who sets the DSCP field? The "end user" can't be allowed to do this because DSCP is used to prioritise traffic, and everyone would set their traffic to high priority. The ideal thing would be to build proxy devices to insert the appropriate value according to a policy. IMHO the obvious location for such a proxy is the Ingress LSR. But the problem is how do you recognise the appropriate traffic types. Cheers, Geoff At 17:14 25/04/01 -0400, Hass, Barry wrote: >Hi Geoff, > >Would it make sense to use the DSCP field for flow aggregation, perhaps >in combination with the IP destination address? > >Barry > >> It makes sense to pursue the idea of data driven LSP setup, but it's >> essential to combine this approach with a flow aggregation mechanism if we >> expect to deploy such a technology in "large networks" (eg. a Service >> Provider). In theory the Ingress LSR could be given the capability to >> aggregate flows of information into a single LSP, but the details of how >> this could be done are generally clouded in marketing smoke and mirrors >> today. The issue is that IPv4 lacks either a flow label (which IPv6 has), >> or a session identifier (that ISO TP4 has) to provide an easy >> classification mechanism. The current "edge LSR" implementations are >> handicapped by these limitations. So how can they assign or aggregate >> traffic? They are normally limited to assignment on the basis of >> destination IP address (essentially useless in most cases), or by the use >> of the Port ID, or by some combination of these two. In other words, >> whatever criteria you can use to build a filter or ACL, you can use to >> assign individual packets to an existing LSP (or as a trigger mechanism to >> create a new LSP). >> > ================================================================ Geoff Bennett Tel: (33) 497 21 43 62 Director of Technology, OCTO Fax: (33) 497 21 43 50 Marconi Gaia - Bat. E email: geoff.bennett@marconi.com BP 123 06903 SOPHIA ANTIPOLIS FRANCE ================================================================ ------- The MPLS-OPS Mailing List Subscribe/Unsubscribe: http://www.mplsrc.com/mplsops.shtml Archive: http://www.mplsrc.com/mpls-ops_archive.shtml
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