Systems and methods for topology discovering in a hybrid fiber-coaxial (HFC) network use multicast messaging to HFC devices, such as RF amplifiers, to initiate and perform topology discovery. HFC devices receiving a multicast message send advertisement messages upstream with at least a device unique identifier and listen for advertisement messages received from downstream HFC devices. Messaging may be implemented using low data rate, low power bidirectional communications with and between HFC devices, for example, according to the LoraWAN remote multicast setup specification TS005. One or more HFC devices that receive device unique identifiers from downstream HFC devices maintain a list of those device unique identifiers. List(s) of HFC devices may be provided to a headend controller and/or a node gateway to compile and maintain topology information, for example, to provide a visual representation of the topology.