Message or traffic data is transmitted from a given radio or node for reception by one or more other nodes in a communications network, by arranging the node for transmitting the data according to a selected one of a number of different medium access protocols. The medium access protocol selected for a given message or traffic is determined according to one or more of (a) the size of the traffic, (b) the priority of the traffic, (c) the periodicity of the traffic, and (d) whether the traffic is broadcast or unicast to the other nodes in the network. Each radio includes one or more processor and memory modules configured to output messages or traffic for transmission from the radio according to the selected medium access protocol. By using distributed scheduling and traffic control to protect against hidden nodes, the radios can maintain agile portability in tactical urban environments.