verlay Connectivity 12.5.3 EVPN 12.6 Future Evolution of Network Edge 12.6.1 Open Packet Processors 12.6.2 Open Configuration and Programing of Packet Processors 12.6.3 Open Control of Packet Processors References INTRODUCTION The network edge provides layer 2 and layer 3 service functions reached by the wired and wire- less access networks. In the canonical reference model, the network edge platform (aka provider edge [PE] sits between the many types of customer access networks (Chapter 11) and core net- works (Chapter 13) and provides service processing, operations, administration and management (OA&M), and traffic aggregation functions (Figure 12.1). In this chapter, we describe the drivers, both business and technical, for the recent rapid evolution of packet edge platforms. In many exist- ing networks, Ethernet is the base link packet technology for service PE networks because Ethernet VLANs are the fundamental unit for grooming and aggregation from the access technologies. Current merchant switches and routers provide very dense and inexpensive Ethernet interfaces to build a high-capacity IP Ethernet fabric to flexibly join access and core through the virtual network function (VNF) service applications. This chapter covers this transition in detail and explores where the boundary between software and hardware implementation can be drawn, SO as to optimize the performance, yet maintain maximum flexibility. 12.2 EDGE CORE PARADIGM Packet edge platforms can be effectively framed in the context of the edge-core paradigm (Figure 12.1), which defines where packet processing function should reside in a network. In this paradigm, the core is purposely kept simple to provide high-speed reliable packet transport (e.g., removing the Internet route table and removing edge label switching functions). In addition to simplicity, the core network generally is not changed by an operations support system (OSS) on a per customer service Building the Network of the Future Access Provider MPLS & Optical Provider Access Platform