Transcript PPT Version

Resource Unavailability PDB
draft-karagiannis-ru-pdb-03.txt
Georgios Karagiannis, Attila Bader,
Hannes Tschofenig, Lars Westberg
Problem to be solved
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Without using signaling, how can a diffserv
node at outside Diffserv domain(s) detect
resource unavailability in Diffserv domain(s)?
Goal of the draft

Draft provides a Per Domain Behavior (PDB)
solution for this problem by using throughput
(bandwidth) measurements and DSCP
remarking in Diffserv domain(s) to notify
resource unavailability to nodes outside the
Diffserv domain(s)
Changes based on received comments

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RU-PDB Applicability section clarified
Traffic Conditioning Specification (TCS) and
PHB configuration clarified
Editorial changes
RU-PDB Applicability
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Resource unavailability on Diffserv nodes detected using
excess traffic measurements and DSCP remarking approach
where remarking proportional to amount of unavailable
resources
Diffserv nodes located outside Diffserv domain(s) can use
remarked DSCP packets to calculate the throughput (or
bandwidth) that exceeds the loosely agreed SLS throughput
bound
Applied in combination with:
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
Single Diffserv domain
Multiple neighboring Diffserv domains when SLA agreements exist
between operator(s) of the domain(s)
RU-PDB Applicability
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Sender of traffic blocks new requests until the loosely agreed
SLS throughput bound is satisfied; this operation is outside
scope of this draft
Applied in any IP based Diffserv scenario that supports realtime applications and use media codecs that do not have the
benefit of being totally free in selecting/producing bit-rates:
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minimum bandwidth allocated by using the DSCP based RU-PDB
mechanism in combination with admission control functionality
when Diffserv network has more capacity it can utilize that and give to
end user higher quality with better end user experience
end to end ECN method (DCCP) can be used to monitor whether the
network has more available capacity.
TCS and PHB Configuration
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Clarified how (1) Meter + (2) Marking + (3) Packet
Classification + (4) Scheduling work
Conclusions and future work:
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Without using signaling but using throughput
(bandwidth) measurements and DSCP
remarking in Diffserv domain(s) able to notify
resource unavailability to nodes outside
Diffserv domains
It can be used in combination with end-to-end
ECN (DCCP) when QoS support for real time
applications that use media codecs is required.