NDP comes up a lot alongside ARP because it essentially replaces ARP for IPv6 networks. Where ARP handles address resolution in IPv4, NDP takes on that role, and more in IPv6. One thing worth clarifying: NDP operates at Layer 3, not Layer 2 or the sometimes-cited “Layer 2.5” like ARP. This is because NDP is […]
If you’ve read the previous article on ARP, you already know how the protocol works, devices broadcast a “who has this IP?” and whoever owns it replies with their MAC address, no authentication involved. That last part is the reason this article exists. No authentication gives us an attack surface. ARP was designed in a […]
We’ve already covered TCP and UDP for data transfer, and how the IP layer wraps them for transport. Now we’re going one layer lower, the link layer, where we need to talk about how IP addresses get mapped to MAC addresses. You can find all the scripts used in this article, as well as the […]