Self-awareness and adaptivity for quality of service

Network self-awareness is the ability of a network to ob-serve its own behavior using internal probing and measure-ment mechanisms, and to make effective autonomous use of these observations for self-management. Experiments are conducted to evaluate the Goal’s impact on observed QoS for the user’s payload. In addition to packet loss due to con-gestion, we also introduce an artificial packet loss at certain nodes to represent failures or other undesirable events. We see that just using delay in the QoS goal is a good way to reduce delay and loss if losses are only the result of conges-tion. However, as one would expect, using loss in the user’s QoS Goal is seen to be useful if the paths which are selected by SPs are to avoid nodes where packet losses are occuring for reasons other than congestion. In general we see a good correlation between the QoS Goal that the SPs use to find paths, and the resulting QoS observed by DPs.