Abstract: A firewall fault-tolerant network interface system includes a switch circuit configured to detect when a firewall fails in a multi-firewall local network. When a failed firewall is detected, the switch circuit waits for a time-out period to expire to allow convergence. The switch circuit then intervenes when traffic from a server to the failed firewall is detected. The switch circuit translates the MAC address of the failed firewall to the MAC address of a functional firewall. Traffic from a server originally directed to the failed firewall is then redirected to a functional firewall. In a further refinement, the switch circuit provides the MAC address of a functional firewall in response to an ARP request from a server to the failed firewall. Thus, traffic from this server will be directed to the functional firewall without further intervention, reducing the overhead of the switch circuit.

Abstract: A firewall clustering system connects two or more firewalls between an internal network and an external network. The plurality of two or more firewalls are combined to supply high-availability and scaling of processing capacity. Firewalls maintain client-server state information. Flow controllers are connected to the firewalls and placed on both the internal “trusted” side and the external “untrusted” side of the firewalls. Flow controllers are placed on both sides of the firewalls to ensure that traffic for a given client-server session flows through the same firewall in both inbound and outbound directions. The firewalls perform filtering operations and/or network address translation (NAT) services. In both cases, the flow controllers supply high availability, scalability, and traffic distribution for the firewalls in the firewall cluster.

Abstract: A router clustering system connects two or more routers to a one or more distinct Internet Service Providers (ISPs) in a complete high-availability arrangement. Typically the two or more routers connect to a plurality of ISPs at a site so that an outage of one ISP does not affect connectivity and availability to the site. The router clustering system typically includes a plurality of clustering units for redundancy that avoids difficulties that arise with a single point of failure. For example two clustering units may be used in an active-passive high-availability configuration. A router cluster creator creates or configures a router cluster. To create a router cluster, an administrator assigns to the cluster a logical Internet protocol (IP) address IPgw and specifies routers that are members of the cluster.

Abstract: A VPN device clustering system connects two or more VPN devices on one side of a virtual private network to a similarly clustered system of two or more VPN devices on the other side of a virtual private network. The VPN device clustering system typically includes a plurality of clustering units for redundancy that avoids difficulties that arise with a single point of failure. For example two clustering units may be used in an active-passive high-availability configuration. A VPN device cluster creator creates or configures a VPN device cluster. To create a VPN device cluster, an administrator assigns to the cluster a logical Internet protocol (IP) address IPvpn and specifies VPN devices that are members of the cluster.

Abstract: A network flow switch system that uses an active flow switch and a passive flow switch in conjunction to achieve redundancy or failover. The flow switches switch information between network components via Y-cables that allow both flow switches to remain simultaneously connected to the network devices. A failover link connects the flow switches together and allows the passive flow switch to monitor the status of the active flow switch. The active flow switch performs all switching while the active flow switch is operational.