Multi-Modal Industrial IoT Networks: Recent Advances and Future Challenges

Abstract While the ongoing fourth industrial revolution continues to be a major driver behind wireless communication technologies, some environments are so prohibitive that even state-of-the-art solutions can barely achieve ubiquitous connectivity (if at all). For example, in sites with large metal constructions (such as petrochemical plants), highly localized and time-varying changes link quality quite common. Oddly enough, much of capabilities needed deal such effects already present physical layer (PHY), but remain largely unexploited by higher protocol layers. In fact, little Industrial Internet Things (IoT) (IIoT) research has considered harnessing full multi-modal modern multi-PHY/multi-band IoT hardware general. As such, this vision paper, we: (1) analyze recent advances towards enabling IIoT through link- routing operations; (2) describe challenges opportunities for future deployments, based on design choices emerged from said analysis. summary, we identify combination modified/extended Time-Slotted Channel Hopping (TSCH) layer, using either fixed or variable duration timeslots, together Parent-Oriented (PO) Routing Protocol Low-Power Lossy Networks (LLNs) (RPL) approach most promising way forward.