D2C: Dynamic Decision Caching Mechanism for Provisioning Safety-as-a-Service in Road Transportation

In this article, we propose a dynamic decision caching mechanism (D2C), for provisioning customized safety-related decision to the end users. The end users may be vehicle owners, drivers, or any government organization. Typically, in a safety-as-a-service (Safe-aaS), these end users select certain parameters from the web portal. Based on these selected decision parameters, the decision is provided to them. We consider road transportation as the application scenario of Safe-aaS and design the caching mechanism. In a practical scenario, certain decision parameters such as weather conditions and permissible weight of a vehicle, do not fluctuate with time. Therefore, continuous data transmission, processing, and decision generation consume unnecessary power. The caching of similar decision parameters, which vary slowly with time, is one of the possible solutions. Additionally, the sensor nodes are energy-constrained in nature, hence we take into account these characteristics, delay in delivery of decisions to the end users, and state of end users to propose the dynamic and distributed cache access mechanism. We consider that the edge devices are enabled with cache memory, which results in minimizing the cache access time. Extensive simulation-based analysis of our proposed system, D2C demonstrates that the energy consumption is reduced by 16–53% and cache hit percentage is improved by 28–31%, compared to the existing caching schemes Roy et al. (2018), Abdelhamid et al. (2015), Abdelhamid et al. (2015).