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Proportional Bandwidth Allocation in DiffServ Networks. Usman Raza Chohan 2005-03-0023. Organization of Presentation. IntServ vs. DiffServ Bandwidth Allocation Schemes Objective of Research Challenges Plan of Action. Quality of Service (QoS) in IP Networks. Integrated Services (IntServ)
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Proportional Bandwidth Allocation in DiffServ Networks Usman Raza Chohan 2005-03-0023
Organization of Presentation • IntServ vs. DiffServ • Bandwidth Allocation Schemes • Objective of Research • Challenges • Plan of Action
Quality of Service (QoS) in IP Networks • Integrated Services (IntServ) • Differentiated Services (DiffServ)
Scalability: Signaling, Maintaining per-flow router state Integrated Services (IntServ) request/ reply
marking r b scheduling . . . Differentiated Services • Design Goal • Move Complexity to Edges of the Network • Stateless core routers Edge router: Core router:
How to Allocate Resources in DiffServ Networks? • What should be the fairness Criteria? • Max-Min Fairness • CSFQ (Core Stateless Fair Queuing) • Rainbow Fair Queuing (RFQ) • Proportional Allocation • E. C. Park & C. H. Choi • P.K. Jagannathan et. al.
Max-Min Fairness • Water Filling Analogy
Rainbow Fair Queuing • Example • A: 10 Kbps • B: 6 Kbps • C: 8 Kbps • Each color: 2 Kbps
Proportional Allocation • Why Proportional Allocation? • Do you think min-max fairness is fairness for SLA based networks? • SLA defines Target rate which determines customer’s bill • Current DiffServ Networks are biased in favor of Smaller target rates
E. C. Park & C. H. Choi Adjust Target Rate Mark Priority (In/out) Use RIO for Preferential dropping Estimate Pin Congestion Notification Through Ack
P.K. Jagannathan et. al. Labeling using multiple token buckets Label value depends upon R/SIR ratio Higher Labels= Low Priority Uses RED with n Levels for Preferential dropping
Objective “A New Stateless Proportional Bandwidth Allocation Technique for DiffServ”
Challenges • Scalability (Statelessness) • Signaling overhead • Labeling overhead • Convergence to Fair allocation • Computational overhead
Plan of action • Research Involves • Enhancing or proposing Marking scheme • Enhancing or proposing Active Queue Management Technique • Simulating existing techniques and new technique • Performance Comparison of new technique with other proportional allocation techniques