What is Web Service? What are the key web service technologies? What are the advantages?

In this article I will explain what is Web Service? What are the key web service technologies? What are the advantages?

A Web Service is a software program that uses XML to exchange information with other software via common internet protocols. In a simple sense, Web Services are a way for interacting with objects over the Internet.

A web service is

1. Language Independent.
2. Based on XML (open, text-based standard).
3. Protocol Independent.
4. Platform Independent.
5. It assumes stateless service architecture.
6. Scalable (e.g. multiplying two numbers together to an entire customer-relationship management system).
7. Programmable (encapsulates a task).
8. Self-describing (metadata for access and use).
9. Discoverable (search and locate in registries) - ability of applications and developers to search for and locate desired Web services through registries. This is based on UDDI.

Key Web Service Technologies

1. XML- Describes only data. So, any application that understands XML-regardless of the application's programming language or platform-has the ability to format XML in a variety of ways (well-formed or valid).
2. SOAP- Provides a communication mechanism between services and applications.
3. WSDL- Offers a uniform method of describing web services to other programs.
4. UDDI- Enables the creation of searchable Web services registries.

When these technologies are deployed together, they allow developers to package applications as services and publish those services on a network.

Web services advantages

1. Use open, text-based standards, which enable components written in various languages and for different platforms to communicate.
2. Promote a modular approach to programming, so multiple organizations can communicate with the same Web service.
3. Comparatively easy and inexpensive to implement, because they employ an existing infrastructure and because most applications can be repackaged as Web services.
4. Significantly reduce the costs of enterprise application (EAI) integration and B2B communications.
5. Implemented incrementally, rather than all at once which lessens the cost and reduces the organizational disruption from an abrupt switch in technologies?
6. The Web Services Interoperability Organization (WS-I) consisting of over 100 vendors promotes interoperability.

Web Services Limitations

1. SOAP, WSDL, UDDI- require further development.
2. Interoperability.
3. Royalty fees.
4. Too slow for use in high-performance situations.
5. Increase traffic on networks.
6. The lack of security standards for Web services.
7. The standard procedure for describing the quality (i.e. levels of performance, reliability, security etc.) of particular Web services management of Web services.
8. The standards that drive Web services are still in draft form (always will be in refinement).
9. Some vendors want to retain their intellectual property rights to certain Web services standards.

 Web Service Example

A web service can perform almost any kind of task.

1. Web Portal- A web portal might obtain top news headlines from an associated press web service.
2. Weather Reporting- You can use Weather Reporting web service to display weather information in your personal website.
3. Stock Quote- You can display latest update of Share market with Stock Quote on your web site.
4. News Headline: You can display latest news update by using News Headline Web Service in your website.
5. You can make your own web service and let others use it. For example you can make Free SMS Sending Service with footer with your company’s advertisement, so whosoever uses this service indirectly advertises your company. You can apply your ideas in N no. of ways to take advantage of it.