A Comprehensive Review of Quality of Service Enhancement Techniques in Message Queuing Telemetry Transport Protocols for IoT Applications

Raghad Mohammed Nayef; Abdulrahman Ikram Siddiq; Noaman Mohammad Noaman

doi:10.51173/jt.v8i1.2790

Authors

Raghad Mohammed Nayef Computer Techniques Eng. Dept., Technical Engineering College, Northern Technical University, Kirkuk, Iraq
Abdulrahman Ikram Siddiq Electronic and Control Techniques Eng. Dept., Technical Engineering College, Northern Technical University, Kirkuk, Iraq
Noaman Mohammad Noaman Mechatronics Engineering Department, College of Engineering, University of Technology Bahrain, Salmabad, Kingdom of Bahrain

DOI:

https://doi.org/10.51173/jt.v8i1.2790

Keywords:

MQTT, Internet of Things (IoT), Cooperative Subscribers, Quality of Service (QoS), Publish/Subscribe, Adaptive Communication, Protocol Optimization

Abstract

The most popular messaging protocol in Internet of Things (IoT) networks is the Message Queuing Telemetry Transport (MQTT). It provides three Quality of Service (QoS) levels for reliable data delivery depending on application needs. Therefore, MQTT is widely adopted and supported by major IoT platforms like AWS IoT, Azure IoT Hub, IBM Watson IoT, and Google Cloud IoT. QoS enhancement techniques are needed in IoT networks because IoT devices and their applications operate in highly constrained and dynamic environments where standard communication protocols (like MQTT) alone cannot always guarantee reliability, timeliness, or efficiency. This study presents a comprehensive review of the recent and current literature on QoS enhancement techniques of MQTT-based IoT systems. These techniques are classified into five primary categories, which are; QoS enhancements at the protocol level, QoS enhancements at the network level, QoS enhancements at the broker level, cooperative subscriber approaches, and adaptive approaches based on context or machine learning. The related works belonging to these categories are explored and discussed in detail, focusing on the trade-offs of delivery reliability, protocol overhead, and energy efficiency. In addition, the study identifies the existing research gaps and limitations, and proposes future directions for advancing scalable, intelligent, and context-aware QoS management in MQTT-based IoT applications.

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Author Biographies

Raghad Mohammed Nayef, Computer Techniques Eng. Dept., Technical Engineering College, Northern Technical University, Kirkuk, Iraq

Raghad Mohammed Nayef has a BSc in Computer Techniques Engineering. She is now an MSc student in the Computer Techniques Engineering department in the Technical Engineering Collegein the Northern Technical University in Kirkuk- Iraq.

Abdulrahman Ikram Siddiq, Electronic and Control Techniques Eng. Dept., Technical Engineering College, Northern Technical University, Kirkuk, Iraq

Noaman Mohammad Noaman, Mechatronics Engineering Department, College of Engineering, University of Technology Bahrain, Salmabad, Kingdom of Bahrain

Prof. Noaman M. Noaman has PhD in Electrical Engineering fro Sheffield University in UK.

He is the Associate Dean at University of Technology Bahrain, in the Kingdom of Bahrain.

https://orcid.org/0000-0003-1315-6074

https://www.scopus.com/authid/detail.uri?authorId=36802470600

He has been involved in many CDC programs and awarded entrepreneurship, business development, and career services certificates. He has dedicated his career to helping students and alumni with career services entrepreneurship, soft skills, business development, skills-building workshops, job seeking, professional networking, and other aspects.

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