of Microsoft is a popular platform for appli- cation development that is not written for a particular OS. The Net also provides interfaces for communication between desperate components or applications. Similar to Java, .Net also has a good bundle of interfaces that can make interfacing of NMS with NBI applications much easier. Fundamentals of EMS, NMS and OSS/BSS Some examples of the server that provides the platform for publishing these inter- faces are: Java application servers: Some opensource implementations include JBoss and JOnAS. Both these application servers are production ready and is compliant to Java Enterprise edition specifications. Net Server: Window .Net Server is an example of the application server that fits in the platform category though it is currently not an opensource product. Objects request broker (ORB): This refers to a middleware technology for interaction and data exchange between objects. Opensource implementations of CORBA ORBs are "openORB" and "JacORB." The north bound interface can also be proprietary modules or adapters that convert data from the NMS to the format required by the application that wants to interact with the NMS. For example IBM Netcool Network management product has a set of probes (generic, proprietary, and standards based), gateways and moni- tors that can virtually collect data from any network environment like OSS services or another EMS/NMS application. The gateway itself supports third-party data- bases and applications like Oracle, SQL Server, Informix, Sybase, Clarify, Siebel, Remedy, and Metasolv. 11.9 Design Considerations In addition to the legacy NMS architecture discussed in this chapter, there are additional architectures that are put to use in the development of the NMS. As an example, event driven architecture (EDA) and service oriented architecture (SOA) and how it applies to development of NMS is briefly discussed here. Event driven architecture in simple terms involves the development of compo- nent/application that can trigger or perform actio