As e-commerce services are exponentially growing, businesses need quantitative estimates of client-perceived response times to continuously improve the quality of their services. Current server-side nonintrusive measurement techniques are limited to nonsecured HTTP traffic. In this paper, we present the design and evaluation a monitor, namely sMonitor, which is able to measure client-perceived response times for both HTTP and HTTPS traffic. At the heart of sMonitor is a novel size-based analysis method that parses live packets to delimit different webpages and to infer their response times. The method is based on the observation that most HTTP(S)-compatible browsers send significantly larger requests for container objects than those for embedded objects. sMonitor is designed to operate accurately in the presence of complicated browser behaviors, such as parallel downloading of multiple webpages and HTTP pipelining, as well as packet losses and delays. It requires only to passively collect network traffic in and out of the monitored secured services. We conduct comprehensive experiments across a wide range of operating conditions using live secured Internet services, on the PlanetLab, and on controlled networks. The experimental results demonstrate that sMonitor is able to control the estimation error within 6.7 percent, in comparison with the actual measured time at the client side.
['Jianbin Wei', 'Cheng Zhong Xu']
Measuring Client-Perceived Pageview Response Time of Internet Services