tion. Other access functions can run in the Network Cloud providing management and control functionality, but must typically be located nearby (e.g., under 10 miles) in order to be able to oper- ate in the necessary timescales. Chapter 11 gives a detailed overview of modern access technology and how it is being trans- formed using SDN and NFV technologies and the Network Cloud. 2.5.8 NETWORK EDGE In packet networks, the edge platform is where network connectivity services are delivered. Before the advent of SDN and NFV, this was done using specialized network elements that converted and multiplexed the bit streams of customer access onto interoffice trunks while applying service func- tions. With IP networks, this is done using a router, which implements the provider edge (or PE) functionality. A router was designed in a chassis with processor cards to handle control and manage- ment functions, fabric cards that interconnected cards across the chassis, and line cards that could be used to connect to customers or to other portions of the network (typically PE connects to P core routers). The PE is configured for the type of service purchased such as Internet or private network. With the Network Cloud, three transformations occur. First, physical connectivity is shifted onto a fabric built using merchant silicon that offers higher density and lower cost than the pro- prietary and specialized PE routers. Second, routing functions are disaggregated with control and Building the Network of the Future management shifted to software on the Network Cloud. Third, the customer data plane is split between the fabric and software switching that runs as software. This last part allows a variety of options for providing PE services. For example, instead of deploying a proprietary PE dedicated to Internet or private networking, multiple PE software elements can run within the same server and provide the same services. If logical resource limits or specialized configurations are required, additional PE software can be executed a