Performance models of a proxy cache server: The impact of multimedia traffic

We propose a multi-class queuing network model to study the impact of multimedia traffic on the overall response times to Web requests for cases with and without a proxy cache server (PCS). We find that an increase of multimedia traffic percentage will significantly impact the response times for both cases with and without a PCS. The PCS “hit rate” is identified as one of the factors that impact the performance of a PCS for multimedia traffic. Further, we find that it may not pay to choose an overly-powerful PCS, as the marginal reduction in the overall response time cannot be justified. We show that the required time to travel through the client network represents the dominant factor of overall response time. Although the firm's network bandwidth does not impact the decision of whether to install a PCS, improving it has a significant benefit of shortening the overall response time to users' Web requests.