There are two ways to view the schema of a Web service:
- The first one is to check the roles that each Web service is responsible for
- The second one is to check the protocol stack for Web service
There are three main roles in the Web service's role Web service architecture:
Service Provider It is the provider of the Web service. The service provider implements the service and enables it to be accessed over the Internet.
Service requester It is the consumer of the Web service. The requestor uses an existing Web service by opening a network connection and sending an XML request.
Service registration This is a directory of a series of services that are logically lumped together. This registration provides a central location where developers can publish new services or find existing services. It thus serves as a place for the company and their services to be centrally settled.
Web Service stack The second option to view the Web service schema is to examine the Web service stack. The protocol stack is still being perfected, but it now has four main layers.
The Service Transport layer is responsible for message transmission between applications. Currently, this layer includes Hypertext Transfer Protocol (HTTP), Simple Mail Transfer Protocol (SMTP), File Transfer Protocol (FTP), and some emerging protocols, such as the Block Extensible Switching Protocol (BEEP).
XML message layer This layer is responsible for encoding the message into a common XML format, so that the message can be interpreted by the other end. Currently, this layer includes XML-RPC and SOAP.
Service description Layer This layer is responsible for describing the public interface as a specific Web service. Currently, the service description is handled through the Web Service Description Language (WSDL).
Service discovery Layer This layer is responsible for centralizing services to a common registry and providing simple publish/Discover capabilities. Currently, service discovery is handled through general description, discovery, and Integration (UDDI).
With the development of Web service, more layers may be added, and more technology can be added to each layer.
The following sections discuss the components of the Web service.
A little bit about the service transport layer the bottom of the Web service stack is the service Transport layer. This layer is responsible for the actual transmission of XML messages between the two computers.
Hypertext Transfer Protocol (HTTP) HTTP is currently the most popular choice for service transfer. HTTP is simple, stable, and widely deployed. In addition, most firewalls allow HTTP traffic. This allows XML-RPC or SOAP messages to be impersonated as HTTP messages. This is great if you want to integrate remote applications, but it does bring a lot of security issues.
Block extensible Switching Protocol (BEEP) This is a protocol that is expected to replace HTTP. BEEP is a new protocol that the Internet Engineering Task Force (IETF) is prepared to establish. The BEEP is built directly on the TCP layer and contains many built-in features, including an initial handshake protocol, authentication, security, and error handling. With BEEP, we can create new protocols for a variety of applications, including instant messaging, file transfer, content consolidation, and network management.
SOAP does not depend on any particular transport protocol. In fact, you can use SOAP through HTTP,SMTP, or FTP. Therefore, a promising idea is to use SOAP on top of BEEP.
Original link: http://www.tutorialspoint.com/webservices/web_services_architecture.htm
Web Service guide: The Architecture of Web service
