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COSS Internet System Physical Architecture
As shown in the two diagrams, the COSS Internet system is deployed and configured into a three-tier physical architecture to have availability, scalability, transactional, and security attributes. Below are descriptions of components in the physical architecture.
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Browser: The browser is a software package that runs on a user's PC. On the Web, a browser is a "thin" client because it can download HTML or PDF and render them to be a rich GUI environment. The browser communicates with the Web server via HTTP protocol. Current popular browsers are Microsoft Internet Explorer and Netscape Communicator. |
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Client Application: The Client application is usually called a "thick" client that can connect to the COSS Internet system using standard Internet protocol. The Client application can be written in many programming languages such as .NET, C, C++, and VB. |
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Router, Firewall: The router is a hardware component that connects a Local Area Network (LAN) to the Internet. The firewall is a software service that runs on a dedicated machine to protect the network traffic. |
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Client Tier Server: Client Tier Servers use the Microsoft Windows 2000 Advanced Server running with Network Load Balancing (NLB) and Internet Information Server (IIS) version 5.0. |
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Business Logic Tier Server: Business Logic Tier Servers use Microsoft Application Server running COM+ and load balancing. |
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Primary Database Server: The Primary Database Server provides the main relational database services and data storage. COSS uses a SQL 2000 database server running on Windows 2000 Advanced Server. |
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Backup Database Server
The Backup Database Server provides a redundant system in case there is a failure in the Primary Database Server.
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