Controller area network traffic flow confidentiality

A receiver device included in a bus-based communication system, comprising:

• a receiver;
• and
• one or more processors configured to:
• receive one or more second frames on a communication bus of the bus-based communication system, each of the one or more second frames including a second header, a respective portion of a data link layer payload, and an end-of-frame indication;
• extract, on a data link layer, the data link layer payload from the one or more second frames, the data link layer payload including one or more first frames;
• provide the one or more first frames to a transport layer, each of the one or more first frames including a first header and a respective portion of a transport layer payload;
• extract, on the transport layer, the transport layer payload from the one or more first frames;
• process one or more padding bits, associated with providing traffic flow confidentiality to communication of a payload on the communication bus, from:
• the one or more first frames on the data link layer, when the one or more padding bits are added on the data link layer and not added on the transport layer, or
• the payload on the transport layer, when the one or more padding bits are not added on the data link layer;
• and
• determine the payload based on the transport layer payload.

A method, comprising:

• adding, by a transmitter device of a bus-based communication system, one or more padding bits, associated with providing traffic flow confidentiality for communication of a payload on a communication bus of the bus-based communication system, either:
• to the payload on a transport layer, or
• to one or more first frames on a data link layer,
• wherein the one or more first frames include a transport layer payload associated with the payload;
• transmitting, by the transmitter device, one or more second frames on the communication bus, the one or more second frames including a data link layer payload associated with the one or more first frames;
• receiving, by a receiver device of the bus-based communication system, the one or more second frames on the communication bus;
• and
• processing, by the receiver device, the one or more padding bits:
• from the one or more first frames on the data link layer, when the one or more padding bits are added on the data link layer and not added on the transport layer, or
• from the payload on the transport layer, when the one or more padding bits are not added on the data link layer.