Patent attributes
Two nodes in a communication system exchange link monitoring protocol messages including special metadata that allows each node to determine the status of source NAT on communication links to and from the other node, e.g., if source NAT is present on the communication link, or if there is a change in source NAT configuration (e.g., from enabled to disabled, from disabled to enabled, or from one translation to another translation). The special metadata also allows true source information (e.g., source address and source port number) to be conveyed between nodes even in the presence of source NAT, because the source NAT device does not change the metadata in the message because the metadata is considered to be part of the message payload. In certain exemplary embodiments, knowledge regarding the presence of source NAT devices as well as the true source information conveyed through the source NAT devices via the special metadata can be used in the context of “stateful” routing.
