Age of Information for Quantum Communication Channels with Monogamy of Entanglement

For time-critical applications, the freshness of information often goes hand in hand with confidentiality to ensure the integrity of sensitive data. Quantum communications are expected to provide secure exchanges of information thanks to the principles of quantum mechanics, such as entanglement, to protect against data breaches. In this paper, we analyze an information update system, where communication between a sender and receiver occurs through a quantum channel, and we consider the presence of two malicious eavesdroppers. Quantum communications already allow consent to identify compromised data, but we show that the presence of multiple eavesdroppers is even more thwarted by a property of quantum channels known as monogamy of entanglement, which, in addition to revealing whether data have been intercepted, prevents multiple eavesdroppers from accessing the same content. Through a game-theoretic analysis, we compute the Nash equilibria of multiple eavesdroppers trying to minimize the age of information of the intercepted data, and we show how their inherent anarchy ensures a higher level of protection for the communication.