Man-in Sample Clauses

Man-in the-middle attacks The man-in-the-middle attack is a form of active eavesdropping in which the attacker makes independent connections with the victims and relays messages between them, making the victims believe that they are talking directly to each other over a private connection, where in fact the entire conversation is controlled by the attacker. Analysis shows the proposed protocol can resist the man-in-middle attacks. In the proposed protocol, the user U and the server share a session key SK only after mutual authentication between the user U and the server. So, an adversary Xxxxx cannot impersonate the userU to establish a session key with the server unless she can pass the verification process of the server. If Xxxxx tries to pass the verification, she has to face the ECDLP. On the other hand, for the same reason Xxxxx cannot impersonate the server to share a session key with the userU . In addition, Xxxxx neither can get the session key between the userU and the server nor can intrude into the communication between the user U and the server to intercept the exchanged data and inject false information. Thus, Xxxxx cannot launch the man-in-middle attack to cheat either the userU or the server.

Man-in. The-Middle (MITM) Attack. It is assumed that adversary 𝒜 has access to 𝐼𝐷𝑖 and 𝐼𝐷𝑗 of IoT devices. He seeks to seize and manipulate messages < 𝐴𝐼𝐷𝑖 , 𝑍𝑖 , 𝜏𝑖 , 𝑡1 > and < 𝐴𝐼𝐷𝑗 , 𝑍𝑗 , 𝜏𝑗 , 𝑡2 > to IoT devices and forge an authorized device. Since the adversary does not have long secret key 𝑑𝑖 and 𝑑𝑗 , he cannot retrieve 𝛼𝑖 = 𝑑𝑗 𝜏𝑖 and 𝛽𝑗 = 𝑑𝑖 𝜏𝑗 , and is unable to perform the man-in-the-middle attack.

Man-in the-middle attack (active attack): If an adversary is planning to implement man-in-the-middle attack, he replaces TA = aP with cP and substitutes TB = bP with vP. Then, KAV = ݁ሺܲǡ ܲሻ௔௩௦ ݁ሺܲǡ ܳ஻ሻ௔௦௫ಳ ݁ሺܳ஺ǡ ܲሻ௩௦௫ಲ ݁ሺܳ஺ǡ ܳ஻ሻ௦௫ಲ௫ಳ . The adversary knows v, aP, and PA, hence, he can compute ݁ሺܲǡ ܲሻ௔௩௦ and ݁ሺܳ஺ǡ ܲሻ௩௦௫ಲ . However, if he wants to compute ݁ሺܲǡ ܳ஻ሻ௔௦௫ಳ and ݁ሺܳ஺ǡ ܳ஻ሻ௦௫ಲ௫ಳ, he must know SB or asP from aP and sP , which is a CDH problem.

Man-in the-middle attack (active attack): If an adversary is planning to implement man-in-the-middle attack, he replaces TA = aP with cP and substitutes TB = bP with vP. Then, KAV = 𝑒ሺ𝑃ǡ 𝑃ሻ𝑎𝑣𝑐 𝑒ሺ𝑃ǡ ܳ𝐵ሻ𝑎𝑐𝑥𝐵 𝑒ሺܳ𝐴ǡ 𝑃ሻ𝑣𝑐𝑥𝐴 𝑒ሺܳ𝐴ǡ ܳ𝐵ሻ𝑐𝑥𝐴𝑥𝐵 . The adversary knows v, aP, and PA, hence, he can compute 𝑒ሺ𝑃ǡ 𝑃ሻ𝑎𝑣𝑐 and 𝑒ሺܳ𝐴ǡ 𝑃ሻ𝑣𝑐𝑥𝐴 . However, if he wants to compute 𝑒ሺ𝑃ǡ ܳ𝐵ሻ𝑎𝑐𝑥𝐵 and 𝑒ሺܳ𝐴ǡ ܳ𝐵ሻ𝑐𝑥𝐴𝑥𝐵, he must know SB or asP from aP and sP , which is a CDH problem.