Network-Level Impacts on User-Level Web Performance

This paper uses packet-level ns2 network simulations to study the impacts of TCP and network-level effects on userperceived Web performance in Web proxy caching hierarchies. We model a simple two-level Web proxy caching hierarchy, and study the effects of link speed, propagation delay, request arrival rate, cache hit ratio, and cache management policy on the transfer latency for Web document downloads. The multi-factor experiments show that link capacity, round-trip time, and TCP behaviours all have a significant influence on user-level response time. The simulation results also highlight the relationships between cache hit ratio and user-perceived Web performance.

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