CEaaS: Constrained Encryption as a Service in Fog-Enabled IoT
Pallav Kumar Deb, Anandarup Mukherjee, Sudip Misra · IEEE Internet of Things Journal · 2022
In this work, we present a solution toward facilitating dynamic encryption schemes—Constrained Encryption as a Service (CEaaS)—in fog-enabled IoT environments. CEaaS is a two-level fuzzy inference system (FIS) in the fog layer which offers customized encryption algorithm decisions to the IoT user devices based on the current configuration, data size, and network state. Fog nodes use the two-tier FIS system to determine the category of the requesting IoT device at the first level and then the encryption scheme at the second level. Existing research on encryption focuses on developing new lightweight algorithms as a global solution for all devices without considering the heterogeneity and corresponding communication links. The device and network configurations collectively add operational delays, which elevates time and security threats. Under such circumstances, a solution that considers both the conditions (varying) for determining the appropriate encryption scheme and the key is important. Through extensive implementation and deployment of heterogeneous fog nodes, we observe that CEaaS is feasible for both powerful and resource-constrained IoT user devices with CPU and memory usage as low as 0.24% and 0.9%, respectively. CEaaS also incurs delays in the range of 0.7 s and energy consumption of 0.07 Joules while securing data transmission. With the feasibility of CEaaS, the dynamic encryption schemes ensure secure communications irrespective of the device types in a fog-enabled IoT environment.