CONNET: Self-controlled access links for delay and jitter requirements

Access links are typically the bottleneck between a high bandwidth LAN and a high bandwidth IP network. Without a priori resource provisioning or reservation, this tends to have a serious effect on premium traffic from delay- and jitter-sensitive applications. This paper develops a new reservation-less mechanism for delay and jitter guarantees across "single FIFO queue" access links by controlling interfering non-premium traffic. The mechanism, called CONNET (Controlled NETwork), uses feedback regulation to create self-controlled network services capable of tracking delay and jitter references. We use a control-theoretic approach in designing the feedback loop based on a "black-box" model of the access link in both cases of single and multiple nodes. For robust control, we employ optimal Linear Quadratic Gaussian (LQG) regulator. We evaluate the performance of CONNET using a real testbed implementation showing its superiority to other rate-based schemes (such as CBQ and WFQ) in terms of simplicity, deployability, and accuracy.