An Enterprise Computer Architecture ASIG – Sept 12, 2001

What is it and why do we need it?  Enterprise architecture describes the underlying distributed computing infrastructure.  It helps us manage the impacts of changes. Applications must deal with changes in business processes from above, and changes in technology from below.

Qualities of a good architecture  Adapt to change  Flexible  Good performance  Scalability  Security  Manageability  Reliability  Portability  No vendor lock-in

What’s different about web applications?  State  Authentication / Authorization  Scalability and Performance - Pooling and sharing of resources  Commit / Rollback, even with multiple targets

Application Layers : Standard 3-Tier

J2EE and Component Based Architecture What Services does it offer?  Standardized modular components/reuse  Connection sharing - multithreading  Static and dynamic web pages  Messaging  Database Resource pooling  Platform independence

Client Windows NT Windows 2000 Netscape 4+ IE 4.5+ Mac javascript Apache v Authentication Server (LDAP) Y/N + UID TC Database Oracle 8.x App Server WebLogic 5.1 EJB Time Collection Technical Architecture PS HR/Payroll Database Labor Accounting Financial Aid PPPL SSL digital certificate * so you don’t have to close browser Batch Processes SQR Staging Area Maestro Unix script SQR Secure web site?