Abstract: An apparatus and method for traversing a network address translation/firewall device to maintain a registration between first and second devices separated by the firewall device are provided. In one example, the method includes intercepting a registration message from the first device to the second device. A determination is made based on a first timeout period defined by the second device as to whether it is time to renew the first device's registration. If it is time to renew the first device's registration, the registration message is forwarded to the second device. A response message that includes the first timeout period is intercepted, and the first timeout period is replaced with a second timeout period based on a binding lifetime of the firewall device before forwarding the response message to the first device.

Abstract: A method is described for detecting rogue packets in real-time protocol (“RTP”) data streams. Rogue packets occur due to a malfunctioning device continuing to send RTP packets after the termination of the media session, or by third party devices due to malfunction or malicious activity. The method recognizes rogue RTP packets by examining identifying fields in each packet associated with the RTP stream. The fields can be in the header of the packet or in the payload, and can include information such as destination address, destination port, protocol, sequence number, SSRC number, and others. Once rogue activity is detected the method can quarantine the associated pinhole information and/or alert a network operator.

Abstract: A method and system are described for resolving problems created by implementing multiple networks using private IP addresses and layer two tunneling protocols is described. A network processing system is operable to map flows from private IP addresses and ports on layer two tunneling protocol networks to public IP addresses and ports using the private IP addresses and ports and identifiers for the layer two tunneling protocol network. The network processing system uses its own public IP addresses and ports to anchor the traffic from the private network and performs the required mapping to pass traffic between the public and private networks.

Abstract: A redundancy architecture is described for network processing systems which allows the network to recover from failure of a network processing system without interruption in service. The redundancy architecture allows network processing systems that use state information to associate network traffic into discrete flows, to provide system level redundancy to prevent service outages, or loss of network traffic resulting from a failure in any single network processing system. The redundancy architecture includes an out-of-band network link between the redundant network processing systems. The out-of-band network link allows the network processing systems to exchange state and other data as necessary.