ons computing architecture) is one such standard in telecom space. Most OSS solutions are expected to have a standard set of interfaces that make it easy to use it, such as a COTS product. The move to comply with standards is also a driver in changes to OSS space. Increasing network complexity: In addition to convergence at domain and technology level, there is also convergence in functionality at network ele- ment level that adds complexity to the network. A typical example of this is an L3-L7 switch in a converged network. In addition to the basic switch- ing operation, the switch would be performing multiple other functionalities including authentication, encryption, and application routing. The support What Is OSS and BSS? systems need to be able to handle the changed network with complex ele- ments having an aggregate of functionality and a complex information base. Emerging standards for service providers: The deregulations and defining of standards for interoperability is a big influence in changing the OSS industry from legacy modules to interoperating standards compliant modules written by different vendors. Open OSS solutions are also available for download, changing the competition landscape in OSS space. Customer oriented solutions: Customer focused modules are also becoming popular in support systems. Customer management and assurance of ser- vice is becoming an integral part of business support systems. This change in focus can be seen even in management standardizing forums with work groups specifically for customer centric management. 19.4 What Do Support Systems Offer? The support systems handle the customer, the services that are offered to the cus- tomer and the resources that offer the services (see Figure 19.1). Managing the customer is a part of the business support while billing is a business operation of the service management that finally applies to the customer. So in most scenarios the three entities that influence the support systems are the resource/infrastructure service, and custome