A Novel Probabilistic Key Management Algorithm for Large-Scale MANETs

Abstract

Mobile ad hoc networks (MANETs) have become very interesting during last years, but the security is the most important problem they suffer from. Asymmetric cryptography is a very useful solution to provide a secure environment in multihop networks where intermediate nodes are able to read, drop or change messages before resending them. However, storing all keys in every node by this approach is inefficient, if practically possible, in large-scale MANETs due to some limitations such as memory or process capability. In this paper, we propose a new probabilistic key management algorithm for large-scale MANETs. To the best of our knowledge, this is the first method which probabilistically uses asymmetric cryptography to manage the keys in MANETs. In this algorithm, we store only a few keys in each node instead of all. We analytically prove that the network will remain connected with a high probability more than 99.99%. Furthermore, we analytically calculate the average path length in the network and show that this parameter will not have a significant increment using our algorithm. All analytical results are also validated by simulation to make them dependable.

Performance Evaluation of QOS Parameters of Hybrid ACO/PSO for Mobile ADHOC Networks

“…Finally, simulation and numerical results were provided to validate the efficiency of their capacity model and to illustrate their theoretical findings. M. Gharib et al [11] proposed a new probabilistic key management algorithm for large-scale MANETs. To the best of these knowledge, this is the very first method which probabilistically used asymmetric cryptography to control the keys in MANETs.…”

Expert key selection impact on the MANETs' performance using probabilistic key management algorithm

“…So, there might not be a direct path between the source and the destination nodes or no path at all. In our previous work we proposed a novel probabilistic key management algorithm for large scale MANETs [1] that uses asymmetric cryptography. This algorithm is probabilistic, so the existence's probability of a path from a specific node to another one may not equal to one.…”

“…Note that there is no relation between the geographical position of the nodes in the underlay and their position in overlay layer. Using such an algorithm in the network, it was proven that the average overlay connectivity probability is more than 99.99% [1], considering the underlay layer as a fully connected network. This probability can be calculated by the Eq.…”

“…In this section, several scenarios are proposed which can be implemented for choosing the more proper k public keys rather than completely random ones as it was described by our previous work in [1]. Choosing public keys expertly to store in each node, may lead to enhancement of some performance parameters such as path length and connectivity probability between nodes.…”

“…Thus, the cryptography problem in MANETs can be reduced to managing the keys in the network efficiently. A probabilistic algorithm that uses asymmetric cryptography is proposed in our previous work [1]. In such a probabilistic algorithm, only some of the public keys are stored in each node, instead of storing them all.…”