WCF from theory to Practice (1): Uncovering the Veil of mystery

Introduction

WCF is the abbreviation for "Windows communication Foundation", the original code-named "Indigo", which is a complete set of technical framework designed by MS for SOA (Service Oriented architecture). It enables the development of distributed (distributed) applications, and the difficulty of development is significantly reduced compared to the previous. Net Remoting and ASP.net Xml Web service. It can be said that WCF is the current Microsoft platform under the most advanced SOA framework, and Microsoft in the next period of time in the field of the flagship product. It has a lot of advantages, but I sum up, its biggest feature is 1 full integration of the original. Net remoting,asp.net Xml Web service,msmq,wse,enterprise Service, such as a number of distributed technology, take its essence, Discard the dross. 2 WCF Although the integration of several technologies, but the development of difficulty is not increased, simple and easy to learn. I believe that in the next few years, WCF must be in the tide of SOA to make the most of the skill. This series of articles is divided into two parts from the big direction, the first part is to introduce the theory knowledge of WCF, the second part is to develop a complete project instance with WCF. I hope to learn from the theory and practice of Microsoft this excellent framework.

The starting point and purpose of this paper

Through reading this article, can solve the following several problems

What is WCF?

What can WCF do?

WCF in this lifetime?

Learn what resources WCF has?

This article is suitable for readers

For beginners interested in WCF, it's best to have some basic knowledge of SOA in the past.

What is WCF?

A closer official view is that WCF (formerly code-named Indigo) is a technology set for creating and running distributed systems, using it to create secure, reliable (reliable), cross-platform (transacted messaging along With interoperability) distributed solution. Its service-oriented programming model is integrated. NET platform, such as. NET Remoting,asp.net Xml Web service,msmq,wse, and Enterprise Service, which can support cross application domains (AppDomain), Processes ( process), the network (network) is for data communication, and can be hosted in a variety of hosts (host) such as Iis,windows service,console,windows application. It applies to operating systems such as VISTA,XP and Windows 2003. Microsoft is a flagship product in the SOA field. For more information, see WCF official homepage: http://netfx3.com/content/WCFHome.aspx

What can WCF do?

In Win32, the application is running in process (thread) threads. NET platform, there are AppDomain, in fact, there is a layer of packaging between processes and threads, similar to the concept of child processes, in a process (or application domain) of the object can be directly accessed and controlled, but beyond this scope, can not be directly access and control, So the process (or application domain) has a certain isolation effect, if it is distributed across different networks, different operating systems on different processes, they are more difficult to communicate, and the distributed application requires that the previously isolated scope through a certain contract to connect, so as to achieve multiple systems of communication and collaboration. Of course, the way to achieve this is far more than WCF one, such as in the Win32 era, often using mapped memory files to achieve interoperability between processes, and in Windows programs, the use of Windows Messaging WM can also achieve the communication problems between different processes, but these have limitations, Because they are not good at solving Cross-platform, cross network issues while WCF can.

WCF in this lifetime

Long before the advent of Web service, many enterprises have implemented their own EAI (Enterprise application integration) enterprise application integration, but at this time is not recognized by the technical specifications, so at that time the integration scheme is more decentralized, There is no uniform standard, although some EAI is still relatively successful, suffer from no technical specifications, it is difficult to promote. After the advent of the Web service, thanks to the strong support of the larger manufacturers (including IBM,MS, etc.), SOAP became a recognized technical specification, and soon became a magic weapon to solve this problem. In response to this change, MS has launched its own web service product in the. Net platform, the asp.net Xml Web service, but this framework has some difficult problems in terms of communication security and performance, although it later added WSE to make up for the shortfall, But overall, the lack of asp.net Xml Web service is obvious. In terms of security, WSE has made great improvements to the XML Web service, supporting security standards for network services such as WS, but as an extension of the framework, The latest version 3.0 is still in beta, and the extended framework is little known, and if the server uses WSE, it requires the client to use it, and because the framework is not widely replicated, it is likely to make development and deployment more difficult for client developers. In terms of performance,. NET Remoting technology has a slight advantage over Web service, but it is difficult to learn, most importantly, it does not implement cross-platform operations, and a service written in. NET remoting is difficult to invoke in Java. This makes it less practical, MSMQ supports Message Queuing, but needs to be integrated into other systems, and the traditional enterprise service supports distributed transactions, but there is no cross-platform feature of Web services. At this time, WCF came into being, it integrates the most outstanding MS has been the best distributed system development technology, take its essence, discard its dross, is distributed application development technology synthesizer, it solves the cross-platform problem, while supporting secure communications and distributed transactions. Because of its simple and easy to learn, in the promotion also must be relatively smooth, it can be said that WCF will open up a new era of distributed development technology, the impact should not be under the Web service.