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BPEL standardizes process management

Business process management provides a graphical approach to automating and monitoring business activities, integrating enterprise applications and managing manual tasks. Historically, BPM products have utilized their own proprietary process languages, design tools and engines. Now that BPM is considered a key aspect of service-oriented architecture, the lack of an industry standard is a significant problem.

An upcoming standard called Web Services Business Process Execution Language (BPEL) is an important step toward addressing this concern.

Originally co-written by BEA Systems, IBM and Microsoft, and currently under review and revision by the Organization for the Advancement of Structured Information Standards, BPEL has attracted a lot of attention and industry backing.

Slated for completion by year-end, BPEL should encourage the adoption of BPM and SOA technologies by companies that have hesitated because they were concerned about portability and protecting their investment. It also should result in the proliferation of new products and solutions, giving buyers newfound levels of flexibility and freedom in choosing tools and platforms.

BPEL is a programming language written in XML. With BPEL-based visual process design tools, developers will be able to use drag-and-drop diagrams to create programs that automate interactions between Web services. This activity is often referred to as Web service orchestration. The processes can range from simple to complex, and they can talk to Web services running on any platform, such as Java 2 Platform Enterprise Edition and .Net.

It is important to note that BPEL can only talk to Web services; Web service orchestration is all it does. It is not intended to integrate with resources that do not offer a Web service interface (such as legacy or custom applications). It is expected that BPEL often will be extended with other languages, such as Java, and paired with other technologies to address these needs.

BPEL is well positioned to take advantage of a significant and timely IT trend: SOA, a standards-based organizational and design methodology that more closely aligns IT with business processes. Using standard interfaces and shared Web services that help mask the underlying technical complexity of IT environments, SOA enables greater re-use of IT assets. This can result in more rapid development, and more reliable delivery of new and enhanced business services.

Once a corporation has built up a library of reusable Web services, BPEL will make it fairly straightforward to tie these services together into new applications. But these services will still have to come from somewhere; IT will need to build, expose and manage these services.

Because BPEL assumes that everything is exposed as a Web service, it won’t always help solve these latter problems. A range of other technologies will continue to be relevant for this purpose and in completing the SOA stack. A few examples are enterprise application integration products ——which can handle the sticky data and integration problems——and service bus products, which will provide centralized management and monitoring of a corporation’s Web services.

Just as BPEL is the first step in BPM standardization, it also is just one of several technologies that eventually will make up most SOA deployments.

While there have been previous attempts at creating a standardized business process language, BPEL has attracted an unprecedented level of interest and is the first to gain critical mass among software vendors.

BPEL语言实现过程管理的标准化

业务过程管理(BPM)提供了图形化的方式实现商业活动的自动化和监视。过去，BPM产品利用它们自己专有的过程语言、设计工具和引擎。现在，既然BPM被认为是面向服务架构(SOA)的关键部件，缺乏工业标准就是个大问题。

一个即将到来、称作Web服务业务过程执行语言(BPEL)的标准是解决此问题的重要步骤。

最初由BEA、IBM和微软共同编写、目前由推进结构化信息标准组织进行评估和修改的BPEL吸引了业界极大的关注和支持。

预定要在今年底完成的BPEL将鼓励那些因为担心可移植性和保护投资而犹豫不决的公司采用BPM和SOA技术。它也将导致新产品和解决方案的大量出现，让买家在选择工具和平台时拥有新的灵活性和自由度。

BPEL是基于XML的编程语言。利用基于BPEL的可视化的过程设计工具，开发人员利用鼠标的拖、拽就能生成程序，实现Web服务之间交互的自动化。此活动常常被称为“Web服务管弦乐”。过程可以多种多样，从简单到复杂，能与在任何平台(如Java 2平台企业版和.Net)上运行的Web服务交谈。

请注意，BPEL只能与Web服务交谈，这点很重要。它所做的全都是Web服务管弦乐。它无意整合不提供Web服务接口(如老式的或定制的应用程序)的资源。BPEL可望扩展到其他语言(如Java)和其他技术配合使用，以满足这些需求。

BPEL定位在利用重要的和现时的IT趋势——SOA，一种基于标准的组织和设计方法论，它更紧密地将IT(信息技术)与商业过程结合起来。SOA利用标准化的接口和共享的Web服务，帮助屏蔽基础的IT环境的技术复杂性，从而更大程度地重复使用IT资产。这将带来更快的开发、更可靠地交付新的和增强的商业服务。

一旦公司建立了可重复使用的Web服务库，BPEL就使这些Web服务连在一起构成新的应用程序变得相当简单明了。但是这些服务还必须来自某个地方，IT部门仍将需要编制、公布和管理这些服务。

由于BPEL假设一切东西都按Web服务发布，所以它不会解决后面的那些问题。多种其他的技术还将继续与此目的有关，用于SOA的整体完成。其中的例子包括企业应用集成产品——能处理数据和集成连在一起的问题，以及服务总线产品——提供集中管理和监视公司Web服务。

BPEL只是BPM标准化的第一步，也只是最终构成大多数SOA应用中多种技术中的一个。

尽管以前有过建立标准化商业过程语言的企图，但BPEL引起了空前的注意，是第一个赢得大多数软件厂商支持的语言。