Web Service Design Stages



Several design stages are to be followed to build an effective Web Service. Let's discuss those stages in this article.

Vision Document

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The very beginning stage of web service design is to create a vision document that should hold the details about three key areas.

  • Users – They are the ones that will consume the web services. Their requirements should be fulfilled completely and should be documented clearly.
  • Objectives – The main business objectives should be visualized in the documents. It's purely based on the users. We need to find out who will be using our services and whether they will be paying for it or not. Such things should be clearly described.
  • Functionality – It generally describes what our web service is going to do. It explains the complete functionality of our goal.

Conceptual Design
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In this stage we should plan how the service will actually be used. It will give you a clear picture of what the service must do. It's completely based on the usage scenarios. For example we can express it like case studies done in an environment.
  • Users should be identified
  • Business requirement should be identified in this stage
  • How the user interacts with our service


Above things should be done at this stage, through this we can easily identify the common system access points.

Logical Design

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Various business components will be identified in this stage. Entire functionality will be split up into various logical components. Interaction among those components should be built in this stage. Simply we can say like web service granularity is done in this stage.
  • Logical Components
  • Interactions between them

When you are done with identifying various logical components and how they interact with each other, it will be so much easier to develop physically.

Physical Design

In this stage, the predetermined components will be built here. Three key things should be kept in mind while building the logical components.
  • Performance
  • Scalability
  • Availability

Components should be built in a reliable and robust manner, so that it won't fail at any situation. It should be capable of handling a large volume of transactions.

Architecture

Once the physical implementation is done, we need to find out how the business components are connected to each other. Certain things like where the application should be installed and how the communication occurs between them, those things should be considered in this stage.

Security

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The most important stage of the web service is the security stage. Here we need to concentrate on the security issues that we face in web services. Three main keys that should be handled in a perfect manner are:
  • Authentication
  • Authorization
  • Firewall

Finally the effective and well secured web service is ready to publish in the directory. Hope this article has explained the various stages involved in the web services.