Patterns: Broker Interactions for Intra- and Inter-enterprise

124 Broker Interactions for Intra- and Inter-enterprise

7.1 Selecting an integration technology

With the continuous progress of enterprise computing, more and more

enterprises are finding the need to quickly adopt new technologies and integrate

with existing applications. Furthermore, due to costs and human resource

limitations, it is often not feasible for enterprises to completely discard their

existing infrastructure.

Enterprise application integration (EAI) and Extended Enterprise (EE) allow

disparate applications to communicate with each other. Both domains are very

similar; their differences are limited mainly to the required Quality of Services

capabilities. Some points to consider while deciding on the integration

technology between applications are as follows:

򐂰 The current infrastructure: Do you already have a messaging system on

the enterprise tier? Then it makes sense to go for JMS. Or, if you have a

legacy system such as CICS or IMS, J2EE Connectors might be the better

choice.

򐂰 Time to market: Web service enabling an application is relatively fast with

the Web services development tools available.

򐂰 Future expansion plans: If you plan to expand your enterprise systems in

the future, you need to keep in mind the integration with your current

infrastructure and your planned infrastructure. Web services may provide the

most cost-effective migration path in such a case.

򐂰 Reliability: JMS with WebSphere MQ, for example, can be used to provide

assured transfer of data, even when the enterprise application is unavailable.

򐂰 Transaction support: Web services currently do not offer support for

transactions. If your application needs transactional management, it might be

worthwhile considering technologies that do, such as JMS or J2EE

Connectors.

Currently, the available product mappings for the Integration Application and

Extended Enterprise patterns focus on the use of the following technology

options (Table 7-1).