Chaotic systems, such as Lorenz systems or logistic functions, are known for their rapid divergence property. Even the smallest change in the initial condition will lead to vastly different outputs. This property renders the short-term behavior, i.e., output values, of these systems very hard to predict. Because of this divergence feature, lorenz systems are often used in cryptographic applications, particularly in key agreement protocols and encryptions. Yet, these chaotic systems do exhibit long-term deterministic behaviors - i.e., fit into a known shape over time. In this work, we propose a fast dynamic device authentication scheme that leverages both the divergence and convergence features of the Lorenz systems. In the scheme, a device proves its legitimacy by showing authentication tags belonging to a pre-determined trajectory of a given Lorenz chaotic system. The security of the proposed technique resides in the fact that the short-range function output values are hard for an attacker to predict, but easy for a verifier to validate because the function is deterministic. In addition, in a multi-verifier scenario such as a mobile phone switching among base stations, the device does not have to re-initiate a separate authentication procedure each time. Instead, it just needs to prove the consistency of its chaotic behavior in an iterative manner, making the procedure very efficient in terms of execution time and computing resources.
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Adaptive and Dynamic Device Authentication Based on Lorenz Chaotic Systems
Chaotic systems such as Lorenz functions have been proposed as cryptographic primitives due to their short-range divergence attributes. They are commonly used in pseudo random number generators, key agreement protocols, and certain classes of encryption procedures. These functions are typically used for their chaotic behavior. However, two of their key properties are often overlooked: (1) their long-range convergence behavior is seldom used, and (2) the static nature of their system parameters is disregarded. The static nature of the system parameters, i.e., core secret, renders these functions vulnerable to a number of attacks when they are deployed in security applications. In this work, we examine these usage gaps and discover compelling security applications for these chaotic systems, in particular, Lorenz chaotic systems. In this paper, we propose an adaptive and dynamic authentication scheme based on discrete Lorenz chaotic systems. The scheme leverages Lorenz function's convergence to achieve a fast and lightweight authentication protocol. We also devise a dynamic parameter configuration technique to enhance the security of the protocol.
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- Award ID(s):
- 1745808
- NSF-PAR ID:
- 10065466
- Date Published:
- Journal Name:
- 61st International Midwest Symposium on Circuits and Systems (MWSCAS)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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