Service and Event Design
Few tasks are more important in moving to a loosely coupled architecture than designing services and events. Read on to get some definitions of events, services, and channels, or drill down to learn how iWay technology supports service enablement, service composition, and our support for composite applications.
Events
For our purposes, an "event" is a message that carries a particular type of business data. An "event" is therefore a message that indicates that a real-world business event has occurred.
Events may be high-level, without application dependencies, such as "request customer billing address"; or they may be low-level and application specific, such as "update billing address in SAP". They may be requests for which responses are expected (as is typically thought of in service-oriented architecture), or fire-and-forget notifications that a business event has occurred. They may be delivered synchronously or asynchronously.
Perhaps most importantly, they can be delivered over any communication mechanism, with any enveloping of information. SOAP, EDIINT, ebXML, HTTP, FTP, and many other communication mechanisms may carry any number of different events.
Services
For our purposes, a "service" is a process associated with an event. People often think of services as request-reply, but events need not be: in that sense, service-oriented architecture is a special case of event-driven architecture, and all iWay technology applies to request-reply service-oriented integration as well as event-driven integration.
"Composite services" are a special type of service that builds on other, lower-level services. Much of the effort in service-oriented integration is creating composite services that can be reused by a variety of other applications.
Any Service on Any Channel
A "channel" is a specification of events and their characteristics (e.g., protocol, IP address, content, etc.) that communicate events in a particular way.
More than one service can be associated with a type of event, depending on the channel that the event is received on – for example, when an "insert purchase order" event comes from a preferred customer, it may invoke a different service than when it comes from a standard customer.
iWay Software's most important characteristic is our ability to associate any service with any channel. Our technology supports more types of channels and a broader array of services than any other vendor.
