opers and service providers. There is coupling between the different SID domains with a high degree of cohesion within the domain (see Figure 24.1). Use of SID leads to business benefits relating to cost, quality, timeliness, and adaptability of enterprise operations. With standard information and interface models, service providers can focus on value creation for their customers without worrying about the interoperability between applications. The most compelling requirement in enterprises of achieving business and IT alignment can be achieved with the SID model apart from satisfying the NGOSS information and data needs. SID derives its roots from the eTOM that provides a business process reference framework and common business process vocabulary for the communications industry. The eTOM offers enterprises an effective way to organize their business processes and the communication between these pro- cesses. The companion model to the eTOM, the SID business view model provides an information reference model and a common vocabulary from a business entity perspective. The SID uses the concepts of domains and aggregate business entities (or subdo- mains) to categorize business entities, thereby reducing duplication and promoting reuse. The SID scheme is categorized into a set of layers. This allows a specific team to identify and define specifications on a layer with minimal impact on other layers. Fundamentals of EMS, NMS and OSS/BSS Mapping Stategy, infrastructure, product Operations Market/sales, product, and customer Service Resource Supplier, partner Enterprise Figure 24.1 SID domains mapped on eTOM level 0 model. This allows independent definition allowing distributed work teams. It should be considered that there is not necessarily a one-one relationship between the layers in SID. The eTOM together with the SID model provides enterprises with a complete view of their business considering both process and information perspectives. SID provides the definition of the affect of information entities on the busines