Towards Semantic Communication Protocols for 6G: From Protocol Learning to Language-Oriented Approaches
This work addresses the need for adaptive communication protocols in 6G networks, but it is incremental as it primarily provides a categorization and analysis rather than introducing a new method.
The paper tackles the challenge of designing flexible medium access control (MAC) protocols for 6G systems to handle non-stationary tasks, by categorizing data-driven MAC protocols into three levels based on their approach, from neural to symbolic to semantic, and explores their opportunities and challenges.
The forthcoming 6G systems are expected to address a wide range of non-stationary tasks. This poses challenges to traditional medium access control (MAC) protocols that are static and predefined. In response, data-driven MAC protocols have recently emerged, offering ability to tailor their signaling messages for specific tasks. This article presents a novel categorization of these data-driven MAC protocols into three levels: Level 1 MAC. task-oriented neural protocols constructed using multi-agent deep reinforcement learning (MADRL); Level 2 MAC. neural network-oriented symbolic protocols developed by converting Level 1 MAC outputs into explicit symbols; and Level 3 MAC. language-oriented semantic protocols harnessing large language models (LLMs) and generative models. With this categorization, we aim to explore the opportunities and challenges of each level by delving into their foundational techniques. Drawing from information theory and associated principles as well as selected case studies, this study provides insights into the trajectory of data-driven MAC protocols and sheds light on future research directions.