Effect of Messaging Model on the Reliable Data Transfer Latency in a Fog System

Fog computing-based IoT paradigm is gaining more importance as it solves high latency challenges of cloud computing-based IoT. Fog solutions promise numerous advantages to real-time IoT services in a heterogeneous network. However, it is essential to achieve effective resource provisioning and reliable data transfer inside the fog to utilize these advantages. In this study, we address the data transfer challenges in a scalable fog architecture and propose a message queue based fast reliable data transmission mechanism. We compare the proposed messaging model with a conventional subscribe-update-notify based data flow approach for the orchestration of reliable data transfer. We provide a comprehensive analysis of timing constraints and delay characteristics of both methods. We then present the performance results of extensive simulation scenarios for up to 100 clients communicating with 256 sensors simultaneously over the proposed platform. The results reveal that the message queue-based approach successfully relieves the latency cost of reliable data transmission in the inner fog.