  High-frequency signals were widely studied in the last decade to identify
grid and channel conditions in PLNs. PLMs operating on the grid's physical
layer are capable of transmitting such signals to infer information about the
grid. Hence, PLC is a suitable communication technology for SG applications,
especially suited for grid monitoring and surveillance. In this paper, we
provide several contributions: 1) a classification of PLC-based applications;
2) a taxonomy of the related methodologies; 3) a review of the literature in
the area of PLC Grid Information Inference (GII); and, insights that can be
leveraged to further advance the field. We found research contributions
addressing PLMs for three main PLC-GII applications: topology inference,
anomaly detection, and physical layer key generation. In addition, various
PLC-GII measurement, processing, and analysis approaches were found to provide
distinctive features in measurement resolution, computation complexity, and
analysis accuracy. We utilize the outcome of our review to shed light on the
current limitations of the research contributions and suggest future research
directions in this field.
