This section presents the architecture of several applications that were implemented using Microsoft® BackOffice® Server and other Microsoft technologies. Each application follows the n-tier development principles set forth in the Windows® Distributed interNet Applications Architecture (Windows DNA) framework. Two of the applications, Island Hopper News and the Fitch & Mather (F & M) Expense Reporting Tool, were developed at Microsoft to illustrate development techniques. The third, the Documentation Review Tool, is an actual tool used by documentation teams at Microsoft for technical reviews.
Each sample application presented as a scenario in the BackOffice Developer's Guide (BDG) underwent a development life cycle that we replicate in the guide's organization. At each stage in this life cycle, the BDG developers confronted the array of choices that BackOffice Server offers as a development platform. Choices they planned to make in the beginning were altered in both the design and implementation phases of development. Lessons Learned in part covers the circumstances that led to the choices they finally did make.
The BDG covers an application called the F & M Corporate Media Library (CML) in great detail, discussing the code line by line. While the solutions in this section are not covered in such detail, they still present a portrait of design choices a development team has made while undergoing a process very similar to the one the CML developers underwent.
Each solution uses BackOffice Server technologies to implement Windows DNA architecture; each follows n-tier application development principles that divide the application into user services, business services, and data services. This strategy not only achieves robustness and extensibility, but it also strives for maximum flexibility, permitting developers to extend and modify their code as new technologies become available. A thin client, such as Microsoft Internet Explorer in the user-services tier, for example, reduces complicated installations and configurations. Encapsulating business logic in COM objects packaged as Microsoft Transaction Server (MTS) components allows for better management of resources such as ODBC connections, and for improved memory management as MTS handles the details of object creation and destruction.
A BackOffice Server application, then, is a deployment of technologies that pass data and instructions back and forth among the tiers of the architecture. To accomplish this, developers rely on a combination of COM objects that ship with various BackOffice Server technologies, such as ActiveX Data Objects (ADO), and the customized COM objects that the F & M CML uses.
The sample applications are: