Lightweight cryptographic protocols for mobile devices

Abstract

In recent years, a wide range of resource-constrained devices have been built and integrated into many networked systems. These devices collect and transfer data over the Internet in order for users to access the data or to control these devices remotely. However, the data also may contain sensitive information such as medical records or credit card numbers. This underscores the importance of protecting potentially sensitive data before it is transferred over the network. To provide security services such as data confidentiality and authentication, these devices must be provided with cryptographic keys to encrypt the data. Designing security schemes for resource-limited devices is a challenging task due to the inherit characteristics of these devices which are limited memory, processing power and battery life. In this dissertation, we propose lightweight polynomial-based cryptographic protocols in three environments that encompass resource-constrained devices which are Wireless Sensor Network (WSN), Fog Computing, and Blockchain Network. With polynomial-based schemes, we guarantee high network connectivity due to the existence of a shared pairwise key between every pair of nodes in the network. More importantly, the proposed schemes are lightweight which means they exhibit low memory, processing and communication overheads for resource-constrained devices compared with other schemes. The only problem with polynomial-based schemes is that they suffer from node-captured attacks. That is, when an attacker captured a specific number of nodes, the attacker could compromise the security of the whole network. In this dissertation, we propose, for the first time, polynomial-based schemes with probabilistic security in WSNs. That is, when the attacker captured a specific number of sensor nodes, there is a low probability the attacker could compromised the security of the whole network. We show how we can modify system’s parameters to lower such attacks.