Method for the secure unindirectional transmission of signals

摘要

A method transmits a signal using a unidirectional communications link, which is protected by an asymmetric cryptography method. A counter value is incremented by a transmitter during a transmission operation. Subsequently, a challenge is determined by the transmitter on the basis of the counter value and a control command that can be executed by a receiver and, on the basis of the challenge that is determined a response is in turn determined. The challenge and the response are transmitted from the transmitter to the receiver. The challenge received is then checked by the receiver to see whether the counter value used in the challenge is greater than a counter value previously stored by the transmitting transmitter. The response received is checked on the basis of the challenge. Following successful checking of the challenge and response, the control command transmitted in the challenge is executed.

主权项

1. A method for transmitting a signal via a unidirectional communications link, protected by an asymmetric cryptography method, comprising:
incrementing, at a transmitter, a counter value, the counter value being incremented based on occurrence of a transmission procedure; determining, at the transmitter, a challenge based on the counter value and a control command executable by a receiver; determining, at the transmitter, a response based on the challenge using a private key of the asymmetric cryptography method; deriving an integrity key at the transmitter based on the response, and generating a cryptographic checksum with the integrity key via the challenge to protect the integrity of the challenge; and transmitting the challenge, the cryptographic checksum, and the response, from the transmitter to the receiver.