Abstract: Various example embodiments for supporting firewalling of traffic are presented. The support for firewalling of traffic may include support for firewalling of layer-2 traffic (e.g., applying firewall rules to layer-3 traffic embedded within layer-2 frames) using a layer-2 firewall. The firewalling of layer-2 traffic by a layer-2 firewall may include support for firewalling of layer-2 traffic associated with various types of layer-2 services. The firewalling of layer-2 traffic by a layer-2 firewall may include support for firewalling of layer-2 traffic for which the layer-2 destination address of the traffic is known and layer-2 traffic for which the layer-2 destination address of the traffic is unknown. The firewalling of layer-2 traffic by a layer-2 firewall may include receiving, by a router, a packet of a flow of a layer-2 service and supporting, by the router, layer-2 firewalling of the packet at the router while honoring layer-2 forwarding of the packet at the router.

Abstract: 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.

Abstract: Various example embodiments for supporting firewalling of traffic are presented. The support for firewalling of traffic may include support for firewalling of layer-2 traffic (e.g., applying firewall rules to layer-3 traffic embedded within layer-2 frames) using a layer-2 firewall. The firewalling of layer-2 traffic by a layer-2 firewall may include support for firewalling of layer-2 traffic associated with various types of layer-2 services. The firewalling of layer-2 traffic by a layer-2 firewall may include support for firewalling of layer-2 traffic for which the layer-2 destination address of the traffic is known and layer-2 traffic for which the layer-2 destination address of the traffic is unknown. The firewalling of layer-2 traffic by a layer-2 firewall may include receiving, by a router, a packet of a flow of a layer-2 service and supporting, by the router, layer-2 firewalling of the packet at the router while honoring layer-2 forwarding of the packet at the router.

Abstract: 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.