Performance and Service Level Considerations for Distributed Web Applications

This paper presents an overview of key factors a ecting performance of Web sites which may be using Web services protocols. We show how Web sites can be scaled with load balancers sending requests to multiple servers which can be distributed for both improved performance and availability. Caching, load balancing, and replication are critical components for achieving good performance and high availability. We also explain how service level agreements can be used to specify, enforce, and di erentiate quality of service within a distributed Web application.