Abstract: A communication network authenticates the source of messages transmitted on a flat bus to determine the presence of spoofing events. A programmable intrusion detection device is connected to the bus at a fixed location and compiles templates for various tri-bit signal pulses that form the data transmitted as messages between network nodes. Each tri-bit template compares unique signal characteristics inherent in the signal waveform received by the device from each node, the unique characteristics being directly attributable to the physical topology of the network. In use, the device uses the templates to calculate an inferred source identifier for each message. The inferred source identifier is then compared against the declared source identifier, which is embedded in message metadata, to authenticate the message source. Any lack of reconciliation between the inferred and declared source identifiers causes the device to mark the message as spoofed and initiate a designated response.

Abstract: A communication network authenticates the source of messages transmitted on a flat bus to determine the presence of spoofing events. A programmable intrusion detection device is connected to the bus at a fixed location and compiles templates for various tri-bit signal pulses that form the data transmitted as messages between network nodes. Each tri-bit template compares unique signal characteristics inherent in the signal waveform received by the device from each node, the unique characteristics being directly attributable to the physical topology of the network. In use, the device uses the templates to calculate an inferred source identifier for each message. The inferred source identifier is then compared against the declared source identifier, which is embedded in message metadata, to authenticate the message source. Any lack of reconciliation between the inferred and declared source identifiers causes the device to mark the message as spoofed and initiate a designated response.