Routed network design is at the heart of the CCDE. Understanding the concepts and principles of Layer 3 design, focused on routing, is critical to achieving the CCDE certification. This chapter discusses the general principles of routed network design. Included are sections on route aggregation, fate sharing, redundancy and resiliency, convergence tuning, configuration complexity, and multicast design principles. Then Chapter 7, “Topology Design Theory,” discusses specific topologies and how they interact with the routing protocols.
Route aggregation serves two specific purposes in a network:
• Breaking the network into multiple failure domains
• Reducing the amount of information the ...