Episode 155: Dynamic ARP Inspection, DHCP Snooping, and Control Plane Policing

Advanced network protection mechanisms focus on securing internal traffic and device behavior. This episode introduces three such features: Dynamic ARP Inspection (DAI), DHCP Snooping, and Control Plane Policing (CoPP). DAI helps detect and block ARP spoofing attempts by validating ARP packets against known trusted entries. This is especially important in VLAN-segmented environments where one compromised host can poison entire segments.

Next, we cover DHCP Snooping, which prevents rogue DHCP servers from assigning false IP configurations by limiting DHCP responses to trusted ports. Lastly, we explain CoPP—a method of rate-limiting traffic directed at the control plane to protect CPUs from overload during attacks. Together, these technologies form a powerful triad of internal protection. This episode helps you move beyond basic firewalling and into granular switch and router defenses.