Asp. NET Create Web Services overview

An XML Web service is a programmable entity that provides a particular functional element, such as application logic, and can access many potentially disparate systems using ubiquitous Internet standards such as XML and HTTP. XML Web services, which rely on widespread acceptance of XML and other Internet standards, use them to create an infrastructure that supports application interoperability, addressing many of the problems that have hindered interoperability in the past.
XML Web services can be used in a single application, or the Internet is used by many applications. Because an XML Web service can be accessed through a standard interface, it allows multiple different systems to collaborate on a single network computation.
XML Web Services do not pursue the ability to migrate code, but rather provide a viable solution to enhance interoperability of data and systems. XML Web services use xml-based messages as a basic data communication method, bridging the bridge between systems that use different component models, operating systems, and programming languages. Developers can use the same approach as creating a distributed application using components to create applications that assemble XML Web services from different sources.
One of the core features of XML Web Services is the high level of abstraction that exists between implementing and using services. By using xml-based messages as a mechanism for creating and accessing services, both the XML Web service client and the XML Web service provider do not need to know anything about each other except inputs, outputs, and addresses.
XML Web Services can usher in a new era of distributed application development. There is no longer a contest between object models or a pageant of programming languages. This is done at the expense of application interoperability when the system is tightly coupled with proprietary infrastructure. XML Web services provide interoperability at a new level, completely denying the competition between those counterproductive systems. As the next revolutionary advance of the Internet, XML Web services will become the basic structure of connecting all computers.
Simple Service
The most basic solution to the implementation of the XML Web service is to provide some basic functional modules for the customer to use. For example, an E-commerce application is challenged by the need to calculate charges for different freight modes. Such applications need to obtain the current shipping cost form from each shipping company in these calculations.
Applications can use standard transport protocols such as HTTP to send a simple xml-based message over the Internet to an XML Web service that calculates freight costs. This message may provide the weight and size of the package, the point of delivery and receipt, as well as other parameters such as service levels. The shipper's XML Web service then uses the latest price list to calculate the freight cost, and uses a simple xml-based response message to return this number to the calling application to calculate the customer's overall cost.