ENHANCING THE HIGH AVAILABILITY OF WEB SERVICES WITH REPLICATED SERVICES ON DIFFERENT PROTOCOLS

Now-a-days Service-oriented architecture (SOA) became more popular in distributed and parallel computing systems. The Availability of Web Services (WS) is vet:v essential in order to increase the overall system availability. A slow service is merely equivalent to unavailable service. Enterprise Service Bus (ESB) provides message oriented, event driven and service oriented approach for integrating services. An ESB implements an SOA through middleware that offers management of service communication between client and services. In order to increase the availability of web service we proposed and implemented an architecture and evaluated its performance. In this architecture ESB act as gateway which multicast the client request to the service replication. The service gateway comprise of message collectors, processors and aggregators which help in arranging the messages in order. WS- Replication deploys services in a set of sites. The client send multiple requests to service gateway and the gateway broadcast these request to the service replicas waiting for the response from one or all of the services. The responses are collected by the gateway and analyzed for faults and a faultless response is returned back to the client thereby increasing the availability of the service.