US Patent 11483287 Reliable firewall

Various example embodiments of a reliable firewall are presented herein. Various example embodiments of a reliable firewall may be configured to provide a single, stateful firewall spanning multiple routers. Various example embodiments of a reliable firewall spanning multiple routers may be configured to provide a reliable firewall configured to protect high-availability network services, network services using multipath routing, or the like, as well as various combinations thereof. Various example embodiments of a reliable firewall spanning multiple routers may be configured to provide a reliable firewall by supporting synchronization of firewall synchronization information (e.g., firewall policy information, firewall session state information, or the like, as well as various combinations thereof) across the multiple routers.