Episode 28 — Traffic Flows: designing for north/south versus east/west

Traffic flow direction is one of the fastest ways to interpret a scenario and choose appropriate controls, and this episode builds a practical model for north/south and east/west design. It defines north/south flows as traffic that enters or leaves an environment, typically involving users, the internet, or external services, and it defines east/west flows as traffic moving between internal services, workloads, or segments. The first paragraph emphasizes why these flows demand different control strategies: north/south designs prioritize perimeter defenses, identity verification, and ingress/egress policy, while east/west designs prioritize segmentation, microsegmentation, and limiting lateral movement. It also explains that modern environments often have more east/west traffic than north/south traffic, which means that internal flow control becomes a primary driver for security and performance decisions.