Looking back over the last six years, it is hard to imagine networked computing without the Web. The reason why the Web succeeded where earlier hypertext schemes failed can be traced to a couple of basic factors: simplicity and ubiquity. From a service provider’s (e.g. an e-shop) point of view, if they can set up a web site they can join the global community. From a client’s point of view, if you can type, you can access services. From a service API point of view, the majority of the web’s work is done by 3 methods (GET, POST, and PUT) and a simple markup language. The web services movement is about the fact that the advantages of the Web as a platform apply not only to information but to services.

PHP comes with a built-in web service designed for mobile applications. It is required to run the official Mobile app. Enable it only if you want people to use the official app or if a third party app explicitly requires it.

Mobile websites developed by us have its own benefits in terms of easy discovery, appearing in google search, compatibility with all mobiles and no downloads. We suggest all our client organizations to get mobile website development done in order to be discover-able by their customers on the go.

Web Services are about exchanging data between a server and a client, using a standard XML format to “package” requests and data so that both systems can “understand” each other. The server and the client could both be Web servers, or any other electronic device you care to think of.

Web services are a new breed of Web application. They are self-contained, self-describing, modular applications that can be published, located, and invoked across the Web. Web services perform functions, which can be anything from simple requests to complicated business processes…Once a Web service is deployed, other applications (and other Web services) can discover and invoke the deployed service.

Network-wise, data exchange in a Web Service typically happens via TCP port 80, using standard HTTP protocol POSTs. Put another way, Web Services operate in basically the same way your browser does when it POSTs an HTML form to a site, and receives a Web page in response. The only real difference is that, instead of HTML, Web Services use XML. And this means Web Services can be available anywhere on the Internet, passing through firewalls the same way viewing a Web page does. The data exchange happens at the packaging layer.

On top of the data exchange, you also need information that describes the interface (or Application Program Interface – API) to the service. This makes the Web Service useful to the rest of the Internet, allowing other developers to develop programs that can access your Web Service. This is called the description layer, and the WSDL (Web Service Description Language) standard that will make this happen is under development.

Above that, there’s information that describes the nature of the service itself (not unlike the HTML-descriptive META tags), so that it can be categorised and found on sites that offer Web Service directories. This is the discovery layer, which is currently being addressed by the UDDI (Universal Description, Discovery and Integration) standard.

Both the description and discovery layers are simply XML, governed by a particular format that enables relevant information to be found for all Web Services on the Internet.

The Web needs to be augmented with a few other platform services, which maintain the ubiquity and simplicity of the Web, to constitute a more functional platform. The full-function web services platform can be thought of as XML plus HTTP plus SOAP plus WSDL plus UDDI. At higher levels, one might also add technologies such as XAML, XLANG, XKMS, and XFS — services that are not universally accepted as mandatory.

Below is a brief description of the platform elements. It should be noted that while vendors try to present the emergent web services platform as coherent, it’s really a series of in-development technologies. Often at the higher levels there are, and may remain, multiple approaches to the same problem.

• SOAP (remote invocation)
• UDDI(trader, directory service)
• WSDL(expression of service characteristics)
• XLANG/XAML(transactional support for complex web transactions involving multiple web services)
• XKMS (XML Key Management Specification) – ongoing work by Microsoft and Verisign to support authentication and registration