Various cognitive communications system architectures and their corresponding Protocol Reference Models (PRMs) are disclosed. Such PRMs incorporate a Cognitive Plane in addition to conventional Data and Management Planes. The additional Cognitive Plane functionality may include, for example, spectrum sensing, spectrum management, geolocation, and security functions. The Cognitive Plane may further include a Policy Engine and a Learning and Reasoning Module. In some embodiments, Management Plane functions may be effectively combined to form a database of primitives (and their respective values) called a Management Information Base (MIB). In addition, techniques are provided by which various components of cognitive and non-cognitive, as well as mesh-enabled and non-mesh-enabled nodes in a network, inter-operate with each other. The architectures allow a Spectrum Manager (or Signal Space Manager) to combine information from various network layers (e.g., PHY/MAC Layers, Spectrum Sensing Function, Geolocation Function, and/or Security Sublayers), and to make informed decisions on spectrum utilization.