Hierarchical Scheduling Mechanisms in Multi-Level Fog Computing

Abstract

Delivering cloud-like computing facilities at the network edge provides computing services with ultra-low-latency access, yielding highly responsive computing services to application requests. The concept of fog computing has emerged as a computing paradigm that adds layers of computing nodes between the edge and the cloud, also known as micro data centers, cloudlets, or fog nodes. Based on this premise, this paper proposes a component-based service scheduler in a cloud-fog computing infrastructure comprising several layers of fog nodes between the edge and the cloud. The proposed scheduler aims to satisfy the application's latency requirements by deciding which services components should be moved upwards in the fog-cloud hierarchy to alleviate computing workloads at the network edge. One communication-aware policy is introduced for resource allocation to enforce resource access prioritization among applications. We evaluate the proposal using the well-known iFogSim simulator. Results suggest that the proposed component-based scheduling algorithm can reduce average delays for application services with stricter latency requirements while still reducing the total network usage when applications exchange data between the components. Results have shown that our policy was able to, on average, reduce the overload impact on the network usage by approximately 11% compared to the best allocation policy in the literature while maintaining acceptable delays for latency-sensitive applications.

Scheduling IoT Applications in Edge and Fog Computing Environments: A Taxonomy and Future Directions

“…While constituent parts of each application can be distributed over several FSs or CSs for parallel execution, there are some constraints for the execution of tasks based on their data-low dependency model. Several works in the literature such as [36,66,68,92] discuss modular applications.…”

“…Minimizing the execution time of IoT applications provides users with a better QoS and QoE. This category contains any metrics related to time such as response time, execution time, and makespan used in the literature such as [22,42,92,123].…”

Scheduling IoT Applications in Edge and Fog Computing Environments: A Taxonomy and Future Directions

“…While constituent parts of each application can be distributed over several FSs or CSs for parallel execution, there are some constraints for the execution of tasks based on their data-flow dependency model. Several works in the literature such as [39,70,72,103] discuss modular applications. [24,25,38,137] have considered loosely-coupled applications.…”

“…Minimizing the execution time of IoT applications provides users with a better QoS and QoE. This category contains any metrics related to time such as response time, execution time, and makespan used in the literature such as [24,45,103,135]. IoT devices are usually considered as battery-limited devices.…”

Scheduling algorithms for truly heterogeneous hierarchical fog networks

“…There has been some research in multitier hierarchical fog cloud scheduling. In Reference 43, Peixoto et al propose a component based scheduler for a multi‐tier fog cloud architecture. They study the effect of shifting the application components to the cloud so as to minimize the impact on network usage.…”