Centralized Repository
- Central process acts as control hub
- Central data repository acts as information hub
- Termed client-server when based on standalone processes
- Integrability allows different clients and servers to interoperate
- Depending on persistency requirements:
- A blackboard can store temporary data acting as a communications hub
- A relational database can provide a persistent data store
- In a two-tier architecture the client accesses the database
- In a three-tier architecture a separate server offers task-oriented services
- A transaction monitor can be used to offer
- Resiliency
- Redundancy
- Load distribution
- Message sequencing
- Middleware allows different parts to communicate with each other
- CORBA (OMG)
- .NET (Microsoft)
- RMI (Java/Sun)
Examples
- Window manager
- File server
- Print server
- Collaboration
- WWW
- Modern ERP systems
- Instant messaging
- Revision control (CVS)