Composite Application Model of Safeco

Safeco is an insurance company headquartered in Seattle, which offers cars, homes and small business insurance businesses. Safeco has built a nationwide network of agents. Surveys show that these agents highly endorse the company's current web sales service platform, that it is the industry's best. The front end of this platform is used. NET development, the backend is the IMS application system that has been used for many years.

At the beginning of 2006, Safeco launched the SOA System project in order to improve product development and business process operation level. Even from an IT perspective, this task can be challenging, as new products, solutions, and process optimization projects that we start each time are independent, lacking the amount of precision for system consistency and project boundaries. We must also significantly increase responsiveness to users while reducing the cost of solution implementation, to meet market needs and achieve our financial goals.

Introduction to SOA

SOA is a recipe for business improvement and agility, because its reusable model provides the possibility of implementing new solutions by reusing and extending existing components. Now, through distributed, especially service-oriented technologies, we can give it resources (data and code) reuse capabilities in terms of performance, scalability, reliability, security, and interoperability, and ensure low cost of reuse. By traditional means, each time you configure IT resources in a new location, you need to spend a budget. With the new model, a unified information system can be established logically rather than physically. Specifically, it relies on new agents, services and other technologies that provide access to data and functionality to achieve this goal.

Of course, SOA is not synonymous with service concepts, it is actually a complete, component-composing application model (see Figure 1):

All operations are defined as canonical, tightly bounded activities, such as user interaction, service invocation, or even the entire process.

These activities are loosely coupled (such as the implementation technology of each activity and call stacks can be different, but the connection channel between them is private, security authorization level is unified management).

Each service is an integral part of the entire enterprise business process, and they collaborate to complete complex business functions.

Figure 1 in SOA, the parts of the entire application are loosely coupled

In SOA, an important change in the underlying model is the transformation of existing applications into "Systems of record", which can be understood as the first generation of the original data source or data, and by implementing the Act Service interfaces for activities such as inform and compute are rendered. The key to successful transformation is to separate the state of the business process instance from the content of the business object. The separation of services should not depend on its application environment. For example, they don't need to know why users call them at some point. The goal of the service is to strengthen the integration capability of the whole system; Each service, in essence, can be regarded as a pure data interface layer.

The application environment management of the service is handled by the business process layer (see Figure 2). In general, SOA will depend on the business process engine to implement system function flow.

BAM (Business activity Monitoring) Once the application model layers are loosely coupled. Monitoring of events via message flow is easy to establish. BAM can also associate events with each other even through CEP (Complex event processing).

Figure 2 SOA Application Model

Technology options

Safeco Selected Microsoft's WCF (Windows communication Foundation) Implementation Service layer in its project, IBM's WPS (WebSphere Process Server) implements the process layer and ASP.net implementation presentation layer (see Figure 2).

WCF is one of the most outstanding service containers to date. Microsoft is the first company in the industry to innovate and implement a service container. This container is characterized by the fact that the programming model does not depend on specific technologies: NET write the same code, you can use a variety of distributed technology, but not limited to webservice. As a WCF partner, service Factory helps developers to easily create complete service engineering in a wizard-based on either a WSDL document or a series of classes that define various methods of operation. Java, inspired by WCF, has also released a new component model (SCA). With SCA, any Java code can invoke the distributed technology that was selected at the time of publication. SCA proposes a new assembly-style programming model that allows technicians to quickly integrate services and components (whether in Java, C + +, or BPEL) with the help of dependency injection (Dependency injection pattern). This assembly mechanism for SCA is a good substitute for the past in which the logical (non physical) routing of the runtime was registered. For any system that can be assembled and implemented, middleware technology can be selected at the time of assembly and non development. IBM's WPS is a BPEL-based business process engine, which can be said to be the predecessor of the SCA specification. WPS is not aware of the internal details of the business, it is a process-centric integration platform-the process itself is defined, you can use WBM (WebSphere Business Modeler) This modeling tool to implement and optimize. Therefore, the Assembly of complex solutions should usually be done by the integration technician rather than the business analyst.

As for the selection of ASP.net in the presentation layer, the main reason is that Safeco's development team and the technology have a source, the choice of other technologies, may be in the future to cause passivity. Of course, we still want SOA to remain in the future to allow users the ability to freely choose to implement technology in accordance with their needs and in support of various user interaction capabilities.