TERENA Networking Conference 2000    

Differentiated Services: Design, Implementation and Validation in the Wide Area

Tiziana Ferrari, INFN - CNAF, Italy

The ongoing diffserv experiments carried out by of the TF-TANT task force in the framework of the Quantum Test Programme analyze several diffserv functional blocks like policing, marking, scheduling and packet drop algorithms in a Europe-wide diffserv testbed and on different diffserv router platforms. We provide an overview of these activities and we illustrate in detail the results of one-way delay and instantaneous packet delay variation measurement when applied to the Expedited Forwarding PHB.

QoS measurement was deployed to study the impact of the EF service rate and buffer dimensioning on EF performance. In addition, two different EF scheduling algorithms have been tested and compared: Weighted Fair Queuing and Priority Queuing. Finally, EF has been tested in the wide area to study the effect on end-to-end performance of multiple EF aggregation points, of congestion and of aggregation of multiple EF micro-flows into the same class. The presentation reviews the main achievements in each of these areas.

Full Paper Word '97 (1.06MB - Good Quality Diagrams) - PDF (125KB - Lower Quality Diagrams) - Slides (140KB)



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