rnet Engineering Task Force (IETF); for mobile networks, this is the Third Generation Partnership Project or 3GPP. Optical (ROADM) Network Services Voice Video (IPTV) Router Router Mobile Internet & Public Clouds Private Networking Router Wireline Access (GPON, DSL) Homes, Businesses, Cell Sites, etc. FIGURE 2.1 Illustration of a modern IP network. Building the Network of the Future Application Presentation Session Transport Network Data Link Physical FIGURE 2.2 OSI layers. To help put the transformation of public networking into context, this chapter describes two examples-a traditional "appliance"-based network and a contemporary software-defined and vir- tualized network (software-defined networking [SDN]/NFV) at a high level. This is to convey that the new SDN/NFV network is more than just faster networking and certainly different than previ- ous efforts to add intelligence and programmed control. TRANSFORMING AN ALL-IP NETWORK TO A NETWORK CLOUD Since every part of a modern telecom network can be architected to be all-IP, it can also be trans- formed to a Network Cloud architecture. This transformation needs to be addressed individually for each of the components of the network-customer premise, access, edge, core, and service platforms. This is because, the benefits of NFV and the degree of SDN control varies from part to part. But there is a great deal of commonality-the NFV infrastructure (NFVI), the SDN control framework, cloud orchestration, network management, security considerations, data collection and analysis, and a new operations paradigm for the software-controlled network. This is illustrated in Figure 2.3, where traditional routers are replaced by a network fabric and where the various dedi- cated elements are replaced by software running on common off the shelf (COTS) servers to imple- ment the data, control, and management planes. Optical (ROADM) Network Services on Cloud Voice Fabric Fabric Video (IPTV) (CLOS) (CLOS) Mobile Network Functions on Cloud Internet & Public Clouds vPE (Edge) Priva