 name of the invocation and the parameter types. NGOSS interface: The interfaces represent functionality provided by man- aged software elements that reside in a component. NGOSS interface signature: The interface signature is a set of announcement and interrogation signatures for each operation type in the interface. NGOSS operation: Operation involves interaction through a contract invocation. Operation happens between a client component and a server component that is either an interrogation or an announcement. NGOSS interrogation: Interrogation is similar to an operation, except that it consists of two interactions, one initiated by a client component instance and the second initiated by the server component instance. NGOSS application: This is a container artifact that provides an encapsu- lation of the requirements, specifications, and implementations. The arti- facts define desired functionality from the perspective of service providers that is needed to support a specific business goal within their operating environments. NGOSS service: An NGOSS service can be either a customer facing service or a resource facing service. An NGOSS service is created, deployed, man- aged, and torn down by one or more NGOSS contract operations. 21.8 TAM The telecom applications map is a reference framework on the set of applications that enable and automate operational processes within a telecom operator. TAM is mainly intended to address the need for a common language for information exchange between operators and system suppliers in developing OSS applications. Having common map component standardization for the procurement process is expected to drive license prices down. Having a standard application model will ensure that investment risks and costs are reduced by building or procuring systems technology that aligns with the rest of the industry using a well-defined, long-term Fundamentals of EMS, NMS and OSS/BSS architecture. Some of the advantages in having a common reference application model are: Reduced development 