1. AF Testing Current Status and Perspectives Octavio Medina Julio Orozco ENSTB / IRISA TF-NGN meeting Southampton, UK 18/04/2002

2. What has been done: –Calibration of WRED –Calibration of TCM for TCP What has been tested: –BW distribution among UDP flows –BW distribution among TCP aggregates –BW distribution TCP vs. UDP What has been simulated –Individual TCP behavior –Aggregation –2 level marking Current Status

3.  What’s missing

4. Until now, testing has focused in observing BW sharing among flows. –BW sharing under congestion not only depends on marking, but also on TCP behavior. –Difficult to imagine a large-scale service based on AF capacities. AF offers priority-based packet drop in case of congestion. –Transport protocols don’t know how to take advantage of that. –A PHB for applications? AF-Based Services

5. A service proposal may be imagined for CBR sources. –UDP multimedia flows –Shaped TCP aggregates ? Tests & simulations for the CBR specific case can be specified. –Focus on Assured Bandwidth, forget BW sharing. –Concentrate on multi-layer multimedia needs? Perspectives

6. Interest for an IP+ service has decreased –AF benefits are only seen under congestion. –Congestion not as frequent as before. AF may be an alternative for LBE –Compare complexity to WRR. –Drawbacks related to delay. Can AF improve ECN? Any other possible use of AF? Perspectives