Today, it is possible that you have embarked on one or two SOA project. Of course, it is not surprising, in the world's 11,000 large enterprises, 95% of companies have launched some sort of effort to achieve a SOA.
Market research firm WinterGreen Research senior analyst Susan Eustis, said: "Most of these SOA projects are based on the various departments or the co-ordination within the department as the beginning and then gradually expanded, and then later put the user business management are also included inside. It can be said, SOA before the expansion of its influence, is also trying to start from the very small. "
Academia and industry with research and practice expanded in-depth, the original head enveloped in SOA's dazzling rings are gradually fade. Is probably the only remaining one glorious SOA accepted by the industry to which the truth: For the SOA, the network is everything.
In fact, not every project can match perfectly with the SOA, or that not all projects can make good use of this architecture SOA pattern. Because if it is to reuse a bunch of other projects have built a good service (of course, assumed that the reuse is not difficult to achieve), then, in the SOA project or the initial construction phase of SOA services, often take a surprising price . Moreover, those veteran class technologies, such as. NET and Java, are still popular in the world of SOA. So perhaps there are a lot of people feel that their own. NET or J2EE is running quite well, there is no need to deploy an SOA.
There analyst said: "The good news is, SOA technology is mature enough, because it is constantly in the process of drawing practice, those experiences and lessons, is now a thoroughly tempered." And from MindTree Consulting's CTO Kamran Ozair that: "In the past few years, SOA has been touted become 'the next dream', so many projects and works have been deployed on a Web-based services, but later it was felt that this is not a appropriate development of the road. "
Perhaps the biggest lesson is to learn when not to use a service-oriented approach. "SOA is not an end of the road, when you need to use SOA, often you need to be addressed in the context of a business issue." A manufacturer of digital audio equipment manufacturers Crutchfield's IT director Steven Weiskircher said.
Crutchfield company began SOA's ice-breaking trip was two years ago, when the company upgraded its emergency task directory, access centers, e-commerce and retail order processing procedures, 90% of these programs are custom code. Weiskircher explained that his development team to support reusable code and objects, but also the team most of the developers for Microsoft's programming tools are more familiar with, so they choose based on. NET's service strategy, but later they immediately realized that they had to focus shifted to business goals, rather than the previous technology goals.
"Of course, the principles of software development within a few years and no major changes. Reusability, as well as to protect the sustainability of demand generated by the data, are valuable design principles. Therefore, service is concerned, has its function where it has its place does not apply. " Weiskircher said.
In this one, the delay of service is the key to the problem. "If you put SOA as a Web service, then - different manufacturers have different argument - you should be aware that services will give you a great deal of money. Any transfer is dependent on a number of components, and will impact the network, including latency, jitter and packet loss and so on. because 20 years ago is a simple ASCII transfer files, but now it is often swollen in the XML file. When you another in its add Simple Object Protocol (SOAP) and Web services security standards (WS-ScurITy) when it is possible to increase the delay, because the package alone and parsing SOAP messages, it will cost a lot of processor resources and network Resources. "Weiskircher explained.
In deciding which piece of code should be abstracted when the SOA services also need to consider is that services the benefits of reusable services is greater than the negative impact of delay. If the code is mainly the same machine running the same application, then the best way not to use services; but if the code is a number of distributed applications by reuse, such as a workflow component in business processes , then the code is packaged as a service for the.
"For example, the transaction may be derived from many different sales channels, but in return, the work flow is similar. No matter what sales channels, the typical workflow will include the collection of funds, customer information and user preferences. These are shared reusable business rules and business logic, and Web-based services for these processes will be of great significance. "WeiSkircher said.
Some users told us that many companies may be the existing code is not suitable for SOA. Wachovia in Charlotte, North Carolina, a senior systems architect Tom Caddoo said: "Our system is very sensitive time and delay systems, which tend to bring us a very great loss."
Wachovia Corporation by examining their application and execution environment to begin deploying SOA. Wachovia believes that although they may be tempted to reuse, but not to the cost of sacrificing performance. Wachovia of course, is not willing to ever have to face those inefficient code. "We have also doubt 'is simply all the existing services are packaged as Web services? Or procedures need to be completely redesigned?' But the final results show that our procedures and re-reusable between programs written the ratio is about 50:50. "Wachovia said.
Network is all
When the benefits of reusable gradually the understanding of the time, the network application to have sprung up. How to ensure that these services have been developed over the transmission network it? Especially in that they still continue to horizontal (to use a different program to achieve the same service) and vertical (written procedures to provide new services) to extend the time.
Use XML tools, you can download from the server to the network device XML document. XML Web services use XML to specify the standard header file to describe the general information, is like the usefulness of the same IP header. Whenever the response time of need, such as the Cast Iron Systems application integration suite, Forum Systems Vantage, Intel's XSLT Accelerator (an XML accelerator), as well as IBM's WebSphere DataPower and Cisco's Application Oriented Network line, will provide these functions support.
RouteOne (Michigan auto finance company) Technical Director Subramaniam said: "We have discovered the advantages of DataPower, RouteOne and some business leaders with their co-operation, such as Daimler Chrysler, Ford, GM and Toyota etc., available to car dealers a single, Web-based credit system. auto dealers can enter into the system, customer information, and for credit certification, so the data can be sent to a number of car company. "
The system is RouteOne five years ago, in a traditional enterprise application integration systems (EAI) based on the use of Java built. "But the system is very expensive and requires a lot of hardware to support the operation of the system." Subramaniam added. However, XML's information revolution has already begun, RouteOne eager, even impatient to wait for the completion of Web services standards, such as Web services security standards, to set foot on the road to the XML.
Subramaniam's team from the area of electronic commerce (using the ebXML standard), and Java Message Service and the digital signature was inspired to create a highly secure XML-based information infrastructure. They created a "very lightweight" system, which is now more than 120 banks and financial companies to use.
However, XML digital signature for the hardware devices, is likely to be a disaster. Therefore, RouteOne the target toward the DataPower, and began to use DataPower XML applications for the service, which quickly became the RouteOne SOA system and its application, the core of the workflow.
Recently, Subramaniam extended these XML capabilities of the device, so that they have more uses, and can handle more applications. Its not only deal with XML digital signature, you can also convert the message from one format into another format, for example, the XML format into EDI format. In addition, it also provides, such as XML encryption and other security features, including a processing flow anomalies, such as when the XML file can not verify the digital signature to be effective, they are able to undertake a scheduled task.
Subramaniam said: "In essence, RouteOne to this work through the intelligent application by the network equipment to handle, and create a 'fully hardware-based Enterprise Service Bus'. And they have a high throughput of network equipment, and could well be expanded. "
"The people are not local to XML processing is an important reason is that this will consume many hardware and memory resources, making large-scale application can not run, and scalability is restricted. Therefore, the use of network hardware resources, the need for large-scale processing XML, is very meaningful. Indeed, you can optimize the XML processing, but you have a good understanding of the processing of XML can be well optimized. Now we have the DataPower, why so much trouble ? "he added.
WinterGreen of Eustis is also very fond of this approach, she said: "DataPower has given a lot to our it is very safe, it can be the data packet switches into messages, which is what we want. Yinwei if you are dealing with Yi Xie reusable components, you must want them to be in the form of a message rather than the form of packets.
As Eustis said, when a Web services-based SOA architecture, coupled with XML processors, the message routing becomes a key to the problem. Translated into a message packet, the message became part of the workflow, and is used to implement business logic. This is the true meaning of Web applications, but also the network project team needs to closely monitor the reasons for SOA. "In fact, an XML device configuration should be proficient in routing protocol family on those IT experts in good, but it is not an ordinary programmers can understand." Subramaniam said.
Framework for dispute
Although, based on service-oriented architecture (SOA), Web services are standards-based, but this does not mean that the industry structure will not be a "declaration of war." Many people agree to abide by the basic, proven Web services standards. These include: Web Services Security (WS-securITy), SOAP and UDDI. In addition, a number of widely accepted, including the following criteria: including XML-based Web services, Java API, Business Process Execution Language (Business Process Execution Language), Web services reliable communication (WS-Reliable Messaging), Web services Addressing (WS -Addressing), SOAP attachments (SOAP with Attachments), Message Transmission Optimization Mechanism (Message Transmission Optimization Mechanism) and Web Services Policy (WS-Policy) and so on.
In fact, the framework of the struggle has never ceased, the main bone of contention is how the Web services business should be put together into a complete SOA architecture. There is a framework model - Service Component Architecture (SCA) has been BEA, IBM, Oracle, SAP and Sybase and other companies to support, but there did not support a company. That is Microsoft.
For the Java camp in the enterprises, SCA will bring great help. SCA specifications from the "Optimization of Structured Information Standards Organization" (Organization for the Advancement of Structured Information Standards) is developing, including the service package, a policy framework, several types of mixing and tuning components (Java, C + +, Web Services , COBOL) the technical details, and with Spring framework (a J2EE application framework) integration.
"SCA is a packaged composite application of a basic platform, it really is the next generation of packaged services as components of the method, but this module can be better managed and have been deployed, and as with other services one by one unit together. "Oracle's senior technical experts SOA David Chappell said.
"The SCA closely rely on the Java, therefore, Microsoft still stick to their architecture model: Windows Communication Foundation (WCF)." Microsoft Internet Systems Steven Martin, director of product management, said: "For use only Microsoft's. NET-Crutchfield Company Weiskircher, in 2005, WCF is also a time to test Indigo began to be considered a good choice. based on. NET, WCF to Crutchfield companies to the distribution of the five original application to become a great combination , service-based application procedures, improved the performance of the entire application. ultimately, SOA is 可能 the default architecture for all software, and now we need to do is build a practice had already been Jian Yan, and effective in Jichupingtai, to solve specific business problems. "