The former property is the basis for supporting guaranteed servicetra#c while the later property is important for supporting best-e#ort servicetra#c. The GeneralizedProcessor Sharing #GPS# discipline is proven to have two desirable properties: #a# it can provide an end-to-end bounded-delay service to a session whose tra#c is constrainedbyaleaky bucket #b# it can ensure fair allocation of bandwidth among all backlogged sessions regardless of whether or not their tra#c is constrained. Our analysis demonstrates that SFQ is suitable for integrated services networks since it: (1) achieves low average as well as maximum delay for low-throughput applications (e.g., interactive audio, telnet, etc.) (2) provides fairness which is desirable for VBR video (3) provides fairness, regardless of variation in server capacity, for throughput-intensive, flow-controlled data applications (4) enables hierarchical link sharing which is desirable for managing heterogeneity and (5) is computationally efficient To support heterogeneous services and multiple protocol families in integrated services networks, we present a hierarchical SFQ scheduler and derive its performance bounds. We analyze its single server and end-to-end deadline guarantee for variable rate fluctuation constrained (FC) and exponentially bounded fluctuation (EBF) servers. We present a start-time fair queueing (SFQ) algorithm that is computationally efficient and achieves fairness regardless of variation in a server capacity.
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