Dual-stack networking is a configuration in which IPv4 and IPv6 run side by side on the same host, router, or network. The system can send and receive traffic using either protocol, which helps organizations transition to IPv6 without losing compatibility with older IPv4 services.
In cyber security, dual-stack environments matter because telemetry, firewall rules, and detection queries must handle both address families correctly. The same connection may appear as a normal IPv4 address in one log source and as an IPv4-mapped IPv6 address in another. Attackers can benefit from that inconsistency if defenders only search one format or trust one protocol path. For defenders, the key controls are address normalization, protocol-aware logging, and testing hunt logic against mixed-stack traffic so malicious outbound connections and command-and-control activity are not missed.