“The way we see it, the web service idea is like an emergency relief bill passing through Congress or Parliament. After a natural disaster strikes, the government typically passes a bill authorizing measures to help the damaged community recover. The last ten years of fighting about operating systems, programming languages, distributed object technologies, and application server platforms have been, metaphorically, of course, like a natural disaster. Collectively, the developers of multi-vendor, multi-platform distributed systems certainly constitute a kind of conceptually damaged community in need of assistance. The web service idea, as we define it above, is a relief bill intended to help.”
Enterprise Application Integration:
“The basic ideas described below on this page are:
– Low coupling – use services instead of objects. Allow parts of the system to evolve independently. Avoid high level of coupling between parts of the system. Instead of using distributed objects (which usually requires re-compilation and testing of both sides of communicating systems) – use distributed services. That is, make small independent services which can be developed and tested independently. And define how you can request and receive these services (communication).
– Low-coupling – use multiple transport mechanisms, but avoid transport-protocol-specific formats and binary formats. Instead use some simple common format (for example, XML and SOAP). Also use messaging middleware such as MQSeries (further decoupling, to assist with distributed transactions, etc.).
– Why you should avoid using EJBs. – instead you can use servlets-daemons in commercial application server – or write your own servers.
– Use XML/SOAP.”
[ Enterprise Application Integration via jy ]