Today we enter the fascinating world of Relay attack, a topic that has captured the attention of millions of individuals around the world. From its origins to its impact today, Relay attack has been the object of study, debate and admiration. With a legacy that spans centuries, Relay attack has left an indelible mark on different aspects of society. In this article we will explore the history, importance and repercussions of Relay attack, providing a deeper insight into a topic that continues to generate interest and inspiration today.

A relay attack (also known as the two-thief attack)[1] in computer security is a type of hacking technique related to man-in-the-middle and replay attacks. In a classic man-in-the-middle attack, an attacker intercepts and manipulates communications between two parties initiated by one of the parties. In a classic relay attack, communication with both parties is initiated by the attacker who then merely relays messages between the two parties without manipulating them or even necessarily reading them.
Peggy works in a high-security building that she accesses using a smart card in her purse. When she approaches the door of the building, the building detects the presence of a smart card and initiates an exchange of messages that constitute a zero-knowledge password proof that the card is Peggy's. The building then allows Peggy to enter.
Mallory wants to break into the building.