Internet Protocol (IPv4 and IPv6)¶

IP moves packets and asks nothing about where they say they came from. A source address is a claim, a fragment is trusted to reassemble honestly, an IPv6 host configures itself from whatever router advertisement it hears, and a dual-stack machine runs two of these at once while most monitoring watches only one. Each of those assumptions is a way in: a spoofed source, an abused fragment, a forged advertisement, IPv4 and IPv6 played against each other, every one a route towards redirection or trust collapse.