System and method for secure communication of components inside self-service automats

摘要

Method to secure the communication of components within self-service automats that are linked to each other by a bus system, having a transmitter and a receiver, characterized in that data are exchanged as tupels (C,A,R,N,Z) on the transport layer of the bus system where
C are the message data M encrypted with an encryption key,A are the message data M authenticated with an authentication key,R represents the role of a component on the bus system of active or passive participants,N represents a message counter,Z represents a session counter.

主权项

1. A method for securing communication of components inside a self-service automat that are connected to each other by a bus system, with a transmitter and a receiver, comprising:
encrypting data as tuples (C,A,R,N,Z, {circumflex over (N)}, {circumflex over (Z)}) by a first computing unit including memory and configured to process data; transmitting data as tuples (C,A,R,N,Z, {circumflex over (N)}, {circumflex over (Z)}) from the transmitter to the receiver on a transport layer of the bus system; receiving data as tuples (C,A,R,N,Z, {circumflex over (N)}, {circumflex over (Z)}) at the receiver; and decrypting data received as tuples (C,A,R,N,Z, {circumflex over (N)}, {circumflex over (Z)}) with the first computing unit or a second computing unit including memory and configured to process data; wherein:
C are message data M encrypted with an encryption key;A are message data M authenticated with an authentication key;R represents a participant role of a component on the bus system of active or passive participants;N represents a message counter;Z represents a session counter;{circumflex over (N)} is a message counter for Δ-last messages N;{circumflex over (Z)} is a last session counter for Δ-last messages;the session counters Z and {circumflex over (Z)} are configured to change the encryption key for different sessions; andfor each session the session counter {circumflex over (Z)} for Δ-last messages is transmitted and considered and the session counter Z is transmitted and not considered; the method further comprising:
allowing Δ-last messages to be lost during exchange of the data without informing an application layer;transmitting from the transmitter to the receiver a pair ({circumflex over (Z)}, {circumflex over (N)}) as a current session counter; andchecking the received data for accuracy at the receiver.