> # Scenario 4

> UsedTextbooksOnline is a Web-based company that links stores that sell used textbooks. Databases track inventory information supplied by the stores and supply buyers with a list of stores that carry the requested book, with the price information from each store. A separate database handles the sales made through UsedTextbooksOnline.

> ### Technology Issues

> Technology issues include the reuse of business logic across applications and the deployment of centralized views of company business systems.

> ### Environment

> The current environment includes Windows and UNIX clients. The Windows clients are standardized on Microsoft Office applications as well as specific business intelligence and third-party tools. The external databases are maintained using Oracle9i on Red Hat Linux, and Informix on Windows 2000.

> ### SequeLink® Solution

> The .NET security, in combination with SequeLink authentication process, protects the privacy of the buyers and sellers, as well as securing the integrity of the UsedTextbooksOnline system.

> Figure 2-4. Scenario 4

> In this example, you install the SequeLink Client for .NET on the application server and SequeLink Servers for Informix and Oracle on the database servers.