Abstract: Instead of specifying actual transport layer IP addresses as a basis for a secure tunnel's security association, an approach described herein specifies virtual addresses. Then suitable network appliances intercept and modify packets in order to map between the virtual addresses and actual addresses. The virtual addresses satisfy IPsec or another authentication procedure that checks packets using the security association. The actual addresses are used by transport layer protocols. This overlay approach permits a session to failover from one network connection to another without requiring restoration of the session in a newly created secure tunnel after one of the network interfaces becomes unavailable, thereby obsoleting the security association based in part on the IP address of the now unavailable interface. This innovative approach also allows the use of parallel paths and the use of one-to-many or many-to-one path topologies, which would otherwise not be permitted.

Abstract: Tools and technologies geographically extend local area networks by transparently inserting transmission of encapsulated local area network frames over wide area network connections. Some devices receive frames from a switch or other physically addressed device using layer 2 protocols, encapsulate them, and send them over a wide area network to a similar remote device which decapsulates the frames and forwards them using layer 2 protocols. Load balancing, quality of service, compression, encryption, and other packet processing may be performed on the encapsulated packets.

Abstract: Tools and technologies geographically extend local area networks by transparently inserting transmission of encapsulated local area network frames over wide area network connections. Some devices receive frames from a switch or other physically addressed device using layer 2 protocols, encapsulate them, and send them over a wide area network to a similar remote device which decapsulates the frames and forwards them using layer 2 protocols. Load balancing, quality of service, compression, encryption, and other packet processing may be performed on the encapsulated packets.

Abstract: Failover controllers help maintain user-perceived continuous connectivity for users of a geographically dispersed flat network when part of that network becomes unavailable, even though flat network packets are not WAN-routable. One such controller has local and remote flat network ports, at least one WAN port, and failover capability to WAN(s) utilizing encapsulation when the flat network is partially or fully unavailable. The failover procedure uses a packet origin table built automatically from incoming packets and from double-tunneled ARP requests. A monitor indicates whether the flat network is fully available (up) or not fully available (down).

Abstract: Instead of specifying actual transport layer IP addresses as a basis for a secure tunnel's security association, an approach described herein specifies virtual addresses. Then suitable network appliances intercept and modify packets in order to map between the virtual addresses and actual addresses. The virtual addresses satisfy IPsec or another authentication procedure that checks packets using the security association. The actual addresses are used by transport layer protocols. This overlay approach permits a session to failover from one network connection to another without requiring restoration of the session in a newly created secure tunnel after one of the network interfaces becomes unavailable, thereby obsoleting the security association based in part on the IP address of the now unavailable interface. This innovative approach also allows the use of parallel paths and the use of one-to-many or many-to-one path topologies, which would otherwise not be permitted.

Abstract: Failover controllers help maintain user-perceived continuous connectivity for users of a geographically dispersed flat network when part of that network becomes unavailable, even though flat network packets are not WAN-routable. One such controller has local and remote flat network ports, at least one WAN port, and failover capability to WAN(s) utilizing encapsulation when the flat network is partially or fully unavailable. The failover procedure uses a packet origin table built automatically from incoming packets and from double-tunneled ARP requests. A monitor indicates whether the flat network is fully available (up) or not fully available (down).

Abstract: Tools and techniques are provided to provide Voice-over-IP (VoIP) communications. On receiving a user request to initiate a telephonic connection from a local site, at which the user is using a VoIP telecommunication device which has no link failover functionality, a system establishes over wide area network links at least two tunnels between a controller at the local site and another controller. Then the system transmits VoIP traffic over at least one of the tunnels from the controller at the local site to the other controller. The system also detects failure of the primary tunnel during the call and performs failover by changing a data path during the call to transmit packets over at least one non-failed tunnel.

Abstract: Failover controllers help maintain user-perceived continuous connectivity for users of a geographically dispersed flat network when part of that network becomes unavailable, even though flat network packets are not WAN-routable. One such controller has local and remote flat network ports, at least one WAN port, and failover capability to WAN(s) utilizing encapsulation when the flat network is partially or fully unavailable. The failover procedure uses a packet origin table built automatically from incoming packets and from double-tunneled ARP requests. A monitor indicates whether the flat network is fully available (up) or not fully available (down).

Abstract: To help maintain secure and convenient connectivity for users when IP addresses change, devices connected between sites by using multiple virtual private network security associations update one another when the security association IP addresses change. The device whose WAN interface IP address changed transmits an address change notification message to the other device over a WAN interface whose IP address did not change. The message indicates which IP address(es) changed and new value(s) to use. The devices can then continue the same secure virtual private network session (from a user point of view above the security association level) by using the new value(s) for the changed IP address(es). Use of the new value for the changed IP address is transparent to (unseen by) VPN applications that are running in the LANs. IPSec sessions and load balancing may be provided.

Abstract: To help maintain secure and convenient connectivity for users when IP addresses change, devices connected between sites by using multiple virtual private network security associations update one another when the security association IP addresses change. The device whose WAN interface IP address changed transmits an address change notification message to the other device over a WAN interface whose IP address did not change. The message indicates which IP address(es) changed and new value(s) to use. The devices can then continue the same secure virtual private network session (from a user point of view above the security association level) by using the new value(s) for the changed IP address(es). Use of the new value for the changed IP address is transparent to (unseen by) VPN applications that are running in the LANs. IPSec sessions and load balancing may be provided.

Abstract: Methods, configured storage media, and systems are provided for resolving domain names into IP addresses in a path-sensitive manner, namely, a manner that may consider information about a link to a server and/or information about routers and other path components. The IP addresses given in response to domain name resolution requests are selected to provide increased reliability and/or dynamic load-balancing over paths.

Abstract: Methods, configured storage media, and systems are provided for resolving domain names into IP addresses in a path-sensitive manner, namely, a manner that may consider information about a link to a server and/or information about routers and other path components. The IP addresses given in response to domain name resolution requests are selected to provide increased reliability and/or dynamic load-balancing over paths.

Abstract: Tools and techniques are provided to provide Voice-over-IP (VoIP) communications. On receiving a user request to initiate a telephonic connection from a local site, at which the user is using a VoIP telecommunication device which has no link failover functionality, a system establishes over wide area network links at least two tunnels between a controller at the local site and another controller. Then the system transmits VoIP traffic over at least one of the tunnels from the controller at the local site to the other controller. The system also detects failure of the primary tunnel during the call and performs failover by changing a data path during the call to transmit packets over at least one non-failed tunnel.

Abstract: Methods, devices, and systems for efficient secure parallel data transmission are disclosed. Data from a local source is divided, with one portion being encrypted and then sent over an open public network, and another portion being sent over a private network without any such supplemental encryption. The portions are thus transmitted at least partially in parallel over networks having different security characteristics, in a manner that helps compensate for the lower security of the open public network without imposing unnecessary encryption overhead on packets being sent over the more secure private network.

Abstract: Methods, configured storage media, and systems are provided for communications using two or more disparate networks in parallel to provide load balancing across network connections, greater reliability, and/or increased security. A controller provides access to two or more disparate networks in parallel, through direct or indirect network interfaces. When one attached network fails, the failure is sensed by the controller and traffic is routed through one or more other disparate networks. When all attached disparate networks are operating, one controller preferably balances the load between them.

Abstract: A controller is provided for increasing bandwidth between a local area network (“LAN”) and other networks by using multiple routers on the given LAN. Data packets are multiplexed between the routers using a novel variation on the standard SYN packet synchronization protocol, and other components. On receiving data destined for an external network, the controller or gateway computer will direct the data to the appropriate router. In addition to providing higher speed connections, the invention provides better fault tolerance in the form of redundant connections from the originating LAN to a wide area network such as the Internet.

Abstract: Methods, configured storage media, and systems are provided for communications using two or more disparate networks in parallel to provide load balancing across network connections, greater reliability, and/or increased security. A controller provides access to two or more disparate networks in parallel, through direct or indirect network interfaces. When one attached network fails, the failure is sensed by the controller and traffic is routed through one or more other disparate networks. When all attached disparate networks are operating, one controller preferably balances the load between them.

Abstract: Methods, configured storage media, and systems are provided for communications using two or more disparate networks in parallel to provide load balancing across network connections, greater reliability, and/or increased security. A controller provides access to two or more disparate networks in parallel, through direct or indirect network interfaces. When one attached network fails, the failure is sensed by the controller and traffic is routed through one or more other disparate networks. When all attached disparate networks are operating, one controller preferably balances the load between them.

Abstract: Methods, configured storage media, and systems are provided for communications using two or more disparate networks in parallel to provide load balancing across network connections, greater reliability, and/or increased security. A controller provides access to two or more disparate networks in parallel, through direct or indirect network interfaces. When one attached network fails, the failure is sensed by the controller and traffic is routed through one or more other disparate networks. When all attached disparate networks are operating, one controller preferably balances the load between them.

Abstract: A controller is provided for increasing bandwidth between a local area network (“LAN”) and other networks by using multiple routers on the given LAN. Data packets are multiplexed between the routers using a novel variation on the standard SYN packet synchronization protocol, and other components. On receiving data destined for an external network, the controller or gateway computer will direct the data to the appropriate router. In addition to providing higher speed connections, the invention provides better fault tolerance in the form of redundant connections from the originating LAN to a wide area network such as the Internet.