A method of detecting nearby monitoring devices by a monitoring device, comprising: using an internal real-time clock to keep track of periodic preselected times for the monitoring devices to attempt to communicate with each other; upon approaching the preselected times, using a processor and short range transceiver to perform the following three stages: a) placing the monitoring device in receive mode for a first selected amount of time before reaching the periodic preselected times and listening for control signals identifying a transmitting monitoring device by nearby monitoring devices; b) placing the monitoring device in receive mode for a second selected amount of time and upon completing without detecting nearby monitoring devices, the monitoring device transmits its control signal; c) placing the monitoring device in receive mode for a third selected amount of time after transmitting the control signal; at any stage while in receive mode upon detecting a control signal transmitted from a nearby monitoring device the monitoring device waits until the end of the transmission of the control signal and records the identity of the nearby monitoring device detected; during the first selected amount of time and the third selected amount of time the monitoring device resumes monitoring in receive mode until completing the respective selected amount of time; during the second selected amount of time the monitoring device restarts stage b after recording the identity of the detected nearby monitoring device, without transmitting the control signal of the monitoring device. using an internal real-time clock to keep track of periodic preselected times for the monitoring devices to attempt to communicate with each other; upon approaching the preselected times, using a processor and short range transceiver to perform the following three stages: a) placing the monitoring device in receive mode for a first selected amount of time before reaching the periodic preselected times and listening for control signals identifying a transmitting monitoring device by nearby monitoring devices; b) placing the monitoring device in receive mode for a second selected amount of time and upon completing without detecting nearby monitoring devices, the monitoring device transmits its control signal; c) placing the monitoring device in receive mode for a third selected amount of time after transmitting the control signal; a) placing the monitoring device in receive mode for a first selected amount of time before reaching the periodic preselected times and listening for control signals identifying a transmitting monitoring device by nearby monitoring devices; b) placing the monitoring device in receive mode for a second selected amount of time and upon completing without detecting nearby monitoring devices, the monitoring device transmits its control signal; c) placing the monitoring device in receive mode for a third selected amount of time after transmitting the control signal; at any stage while in receive mode upon detecting a control signal transmitted from a nearby monitoring device the monitoring device waits until the end of the transmission of the control signal and records the identity of the nearby monitoring device detected; during the first selected amount of time and the third selected amount of time the monitoring device resumes monitoring in receive mode until completing the respective selected amount of time; during the second selected amount of time the monitoring device restarts stage b after recording the identity of the detected nearby monitoring device, without transmitting the control signal of the monitoring device. <EOS>