Department Publications

Congestion in a networked control system (NCS) has many undesirable effects that can make a control system unstable if severe enough. These include delays and packet drops. Therefore, reducing network traffic, including traffic generated by the NCS itself is a necessity. In event based control (EBC) a control signal is generated when a specific event is triggered such as the control error exceeding a predetermined threshold. When the rate of change of a variable is bounded, event triggering reduces the effective frequency in which control signals have to be generated when compared to a system with periodic sampling. This paper proposes a new method of event triggering called event triggered adaptive differential modulation (ETADM) that combines the bandwidth reduction strategies of event triggering and human speech coding techniques. The proposed method can be applied to nonlinear systems with a …

Multi field packet classification is the enabling function for many novel and emerging network applications. Exponential growth of Internet traffic and classification rule sets demand novel hardware based architectural approaches to packet classification. Even though this is an immensely studied area, packet classification that supports scalability in both line rates and rule sets is scarce. In this paper we present experience gained while implementing a parallel packet classification engine architecture on a popular reconfigurable router platform. The architecture exploits parallelism offered in modern hardware technologies to classify multiple packets simultaneously to increase the throughput. The architecture is also capable of utilizing temporal locality present in internet traffic to increase the throughput. The Architecture was implemented on NetFPGA platform and packet classification was done at full line rate without …