Integrating Services in a Service

Integrating Services in a Service-Oriented Architecture

Connected Services Framework 3.0 SP1

When you use the Web service standards of Universal Discovery Description and Integration (UDDI), Simple Object Access Protocol (SOAP) and Web Service Description Language (WSDL), you can create an XML Service Web service integration platform that is based on a service-oriented architecture (SOA). Such an infrastructure and integration platform helps you to Web-enable the application technologies that are found both inside and outside your enterprise. The strength of such a platform is that it can bridge the boundaries between proprietary platforms, languages, and code by using a standard Web infrastructure. A SOA should meet the four tenets of service-oriented architecture, which are outlined in Principles of Service Oriented Design.

When you deploy an integration platform, the primary challenge is to create it. This platform should be flexible enough to not only support the Web services you currently plan to use in your application, but should also support upgrades to those services, and introducing entirely new services in the future. To achieve this, your design and implementation of the infrastructure should be based on the four tenets of service orientation. One of the most important factors is that the components of the infrastructure should be independent of both the services that they support, and the other components within the infrastructure. Because each Web service is completely replaceable, both your application and the infrastructure can be modular.

There are two phases to creating an infrastructure that supports Web service integration with a SOA. The first phase of Web service integration, and a prerequisite for further Web service projects, is to provide a flexible, scalable internal infrastructure platform that supports the requirements of the business as it goes forward.

The second phase extends the platform across your network firewall so that your business can link to suppliers and customers. Applications that are integrated by using Web service standards offer collaboration with outside systems by using the same architecture that you created for your internal systems. Rather than building a point-to-point connection between your customer's systems and each of your systems that they want to use, you can create a single connection to the SOA-based integration platform. For example, suppose a customer requires integration with one of his internal systems so that he can review your production systems, order status, and update his sales ledger information. With the traditional approach you would create at least three separate interfaces, probably on three different platforms. At a later date, if the customer wanted to add a connection to support product lifecycle management, this would entail further integration, and it is unlikely that any of these interfaces could be re-used by another customer or elsewhere in your enterprise.

A Web service integration platform enables you to connect the customer's internal system to your systems with one adapter, so the customer can then access all of the required internal systems through that platform. Other clients who request connectivity can be added in the same way and even reuse the adapter that you developed for the first customer. Security and access control issues can be handled by the firewall and authentication systems.

Such an infrastructure should provide some basic functionality to meet common application requirements. This functionality can include identity management (such as credential authentication and authorization, and federation of identities across heterogeneous domains), user profile management, content-based routing, message security issues (such as encryption and digital signatures), and can allow Web services that participate in the application to drop out and rejoin the application as necessary. Microsoft Connected Services Framework provides a development and execution platform that helps you to create a Web services integration platform that meets these requirements.