Network Virtualisation Design Concepts over the WAN
The desire for segmentation in the network is increasing at a rapid pace. Network segmentation over the WAN using L3 Virtual Route Forwarding (VRF) instances maximizes network hardware, by separating organisations logically, on the same physical hardware, greatly reducing cost and operational complexity. Multi-tenant compute environments in the data centre, traffic separation for security purposes and/or internal organisational separation are some of the key drivers for extending logical network separation over the campus and the WAN. This session will address WAN virtualisation from a network view at Layer 3. We will focus on basic concepts, available IP and Ethernet transport options available from service providers, challenges when implementing IP network virtualisation over the LAN, and recent WAN virtualisation innovations for branch aggregation that will simplify these deployments. In-depth topics include extending VRFs over the various transport options, including 802.1Q, MPLS, and specific to the WAN, VRF-Lite and MPLS over the various IP tunnel solutions that apply for traversing L3 VPN transport offerings offered by service providers. Technologies discussed include, but are not limited to VRF and VRF Lite, MPLS over IP innovations leveraging multi-point GRE tunnels, MTU challenges, QoS deployment models in a virtualised LAN/WAN, as well as options for large-scale Layer 3 MPLS VPN services over GRE/IPSec for extending Layer 3 segmentation across the WAN to branch offices and/or other data centres. This session will also introduce some of the new innovations for Layer 3 including MPLS VPN over mGRE and LISP for L3 segmentation, and touch on Software Defined Networking (SDN) as it begins to evolve. Understanding Data Centre Interconnection (DCI) and L2 segmentation solutions is an important application that utilises WAN virtualisation infrastructures, DCI will not be discussed in great detail in this session. However, there are several related sessions to consider, in combination with this session that may be useful to understanding the broader LAN/WAN virtualization framework for L2 and L3 within the Cisco portfolio.