SEDA is a new strategy for incorporating event driven architecture for scalability and availability of services in the context of SOA. These strategies are based on queuing research pioneered for the use of highly abailable and scalable services, initially in the Web context, but moving into the SOA and Web services context. This article describes SEDA with an implementation in the context of Mule.
Read Using SEDA to Ensure Service Availability.
In SEDA, a request to system or service can be split in to a chain of stages each doing its part of the total workload of the request. Each stage is connected to the others by request queues, and by controlling the rate at which each stage admits requests, the service can perform focused overload management (for example, by filtering only those requests that lead to resource bottlenecks). By choosing this approach a given computer system can scale very well without having the traditional pile of CPU capacity to handle request bursts.