Mitigating Masquerade using Nonce in Symmetric Key Distribution - Survey

Key distribution deals with mechanisms for secure distribution of keys. Since symmetric key cryptography requires both parties(encryption and decryption) to use the same key, the security of key distribution techniques is pivotal to the secrecy of overall exchange. This process generally uses master keys and session keys for key distribution and can be further strengthened by making use of nonces. A nonce is a non-repeating value (number used once) which may or may not be random. Such a value can be incorporated in cryptographic algorithms so as to make guessing and predicting difficult for an adversary during the exchange of messages between two entities over the network. This can help in mitigating masquerading and replay attacks. A masquerade attack is a kind of active attack wherein one entity pretends to be a different entity. Some other kinds of active attacks such as replay attack and modification of messages can also be grouped under the umbrella of masquerade attack. Such attacks often take advantage of the predictable nature of certain steps during the exchange of messages between two entities over the network. In this paper, we explore the usage of nonces in various cryptographic and network security applications in symmetric key distribution environment so as to prevent active attacks like masquerade attacks.