Asp. NET create the XML infrastructure for Web services

To be successful in network diversity, XML Web services must not be concerned with the operating system, object model, and program language that you choose. Moreover, XML Web services, which are as widely accepted as other web-based technologies, must:

Loosely coupled: If only the commands used in the two systems understand the self-describing text-based messages mentioned earlier, then the two systems are considered loosely coupled. On the other hand, tightly coupled systems use a large number of customized software to enhance communication between systems, and need to know more about the system.

Ubiquitous communication: It is now unlikely that individuals will be able to build an operating system or, in the near future, integrate the ability to access the Internet, so this requires an ubiquitous communication channel. Similarly, the ability to connect virtually any system and device to the Internet will ensure that such systems and devices are used by other systems or devices connected to the Internet.

Universal Data Format: By adopting existing open standards rather than dedicated closed-loop communication methods, any system can support the same open standards that can understand XML Web services. Using self-describing text-based messages, XML Web services and their customers can share these messages without having to know the composition of each underlying system, which will be able to communicate across disparate systems independently. XML Web services use XML to implement this functionality.

An XML Web service uses an infrastructure that provides the following functionality: A discovery mechanism for locating XML Web services, a service description that defines how these services are used, and a standard connection format for communication. The following illustration shows an instance of this infrastructure.

XML Web Service Infrastructure

Infrastructure blocks	Functions
XML Web Services Directory	The XML Web service directory provides a central address for locating XML Web services provided by other organizations. XML Web service catalogs such as UDDI registrations implement this function. The client of an XML Web service can reference an XML Web service directory, or it can not reference an XML Web service directory.
XML Web Service Discovery	XML Web service discovery uses Web Services Description Language (WSDL) to locate or discover one or more related documents that describe a particular XML Web service. Disco specifications Define the rules for locating service descriptions. If the XML Web service customer understands the location of the service description, they can bypass the discovery step.
XML Web Service Description	To understand how to interact with a particular XML Web service, you need to provide a description to define the interactive operations supported by the XML Web service. XML Web service clients must understand how to interact with an XML Web service when they can use it.
XML Web Service connection format	In order to be able to make universal communications, XML Web Services communicate using open connection formats, which are protocols that are understandable to any system that supports the most common web standards. Soap is a key protocol for XML Web service communication.

XML Web Services Directory

As with any other resource on the Internet, the XML Web service directory cannot find a particular XML Web service without some lookup methods. The XML Web Services directory provides a central address that allows XML Web service providers to publish information about the XML Web services they provide. Such a directory can even be an XML Web service itself, which can be programmed to access and provide search results to respond to queries from XML Web service clients. It may be necessary to use an XML Web service directory to locate an organization that provides an XML Web service for a specific purpose, or to determine what XML Web services are provided by a particular organization.

The UDDI (Unified Description Discovery and Integration Specification) specification defines a standard method for publishing and discovering information about an XML Web service. The XML schema associated with UDDI defines four types of information, allowing developers to use a published XML Web service. These are information on business information, service information, binding information, and other specifications for services.

As a core component of UDDI Engineering, UDDI Business Registry (business registration) allows business programming to locate information about XML Web services published by other organizations. Developers can use UDDI Business registry to locate discovery files and service descriptions. For more information, see the UDDI Web site (uddi.microsoft.com).