Within the data center, CampusCruiser employs state-of-the-art hardware equipments and software modules. These components are optimally configured to ensure security, high availability, scalability, and performance. To provide effective application services, various dedicated servers run distributed services in clustered, replicated, or fail-over modes (refer to Figure 1). The network architecture consists of Local Area Networks (LANs) and a Storage Area Network (SAN).
High-speed Network and Firewall
CampusCruiser's hosting site is protected from unauthorized Internet traffic by a firewall, plus additional security provided by using load balancers. Inside the firewall are high-speed networks with various servers providing application services. The primary LAN is a 100Mbits/sec switched Ethernet network providing the application network environment. The SAN consists of hosts attaching through a 100Mbytes/sec fiber optic links through fiber switches to an EMC enterprise storage platform. The purpose of this layout is to allow multi-hosts access to a highly available pool of storage.
High Availability and Load Balancing
For each dedicated service in CampusCruiser, the load is distributed optimally among multiple servers using state-of-the-art load balancers. The load balancer also detects system availability using sophisticated load balancing algorithms, and redirects the traffic to alternate servers in the event of a server failure. Furthermore, load balancers provide additional security by using VIP (Virtual IP Address), NAT (Network Address Translation), and SNAT (Secure Network Address Translation).
Web Servers
Web servers consist of high-end multi-core CPU computers with Apache Web Server. These web servers provide the front-end interface to the application server cluster. They manage static HTML pages and implement SSL-based security for sensitive pages. Incoming network traffic is optimally distributed among all available web servers via balancers. Scaling is achieved by simply adding more web servers.
Application Servers
Application servers consist of high-end multiple CPU computers employing BEA WebLogic application server software. The application server cluster utilizes state-of-the-art server side Java technologies, including Java servlets and Enterprise JavaBeans (EJB). Between these multiple application servers, session information is replicated and thus provides load balancing and fail-over capabilities
Database Servers
Database servers consist of high-end multiple CPU computers employing Oracle Database server software. The database is hosted on enterprise SAN platform. High-availability is achieved by using Oracle 10G RAC real-time database replication solution.
Email Servers
Email servers consist of high-end multiple CPU computers with an in-house developed Java-based Email server program. Scalability is achieved by simply adding more Email servers to the cluster.
Chat Servers
Chat servers consist of high-end multiple CPU computers with an in-house developed Java-based chat server program. Scalability is achieved by adding more chat servers to the cluster.
File Servers
File servers consist of high-end multiple CPU computers on the enterprise NAS platform using clustered solution on the SAN.
Other Miscellaneous Services
Other miscellaneous services, such as the weather service, news service, data feed service, etc., are distributed and run among various other servers in the production site.