Analyzing the accuracy of CHOKe hits, CHOKe misses and CHOKe-RED drops

CHOKe, xCHOKe and RECHOKe are preferential dropping schemes that have been proposed for detection, control and punishment of malicious flows at routers in IP networks. They use CHOKe hits, CHOKe misses and/or CHOKe-RED drops to carry out these tasks. In this paper we investigate the accuracy of malicious flow detection by using these hits, misses and drops (using ns-2). We also point out the unreliability of CHOKe hits and misses, when compared to CHOKe-RED drops, as they affect TCP-friendly flows adversely. By doing so, we present two variations of CHOKe called Half1 and Half2 to improve CHOKe and compare them with CHOKe. Half1 and Half2 outperform CHOKe when the combined rates of malicious flows are less or greater than the link capacity respectively.