Range-confined security management adapter and method simplify security deployment in a network. First RC security information, including nearest- and k-neighbor information, is transmitted between authenticating neighbor and supplicant neighbor using a predetermined transmission adaptation technique. The adapter can evoke a response from the neighbor by adapting the initial transmitted signal power level, and increasing incrementally; the initial transmitted signal bit rate, and decreasing incrementally; or both, in response to second RC security information signal. RC communications are effected at low power, high bit rate, or both, establishing secure configuration, effecting secure communication, and thwarting miscreant intrusion into the network.