Comparisons of ZigBee Personal Area Network (PAN) Interconnection Methods

ZigBee's low power consumption, built-in security method and ratified specifications make it very suitable to be used with medical sensor devices. Medical sensors in a human body self organize in a ZigBee Personal Area Network (PAN). At a higher level, these PANs are interconnected in a Healthnet. To this end, a ZigBee PAN detects the existence of another PAN with beacon detection or active channel scan and selects proper target based on the peak energy (when energy detection channel scan is used). Different ZigBee interconnection schemes are then possible. PAN bridge method uses special bridge node that works for different PANs with time division method. PAN merge method changes PAN coordinator's role as bridge node and merges two PANs. Peer-to-peer network can be used when all PANs use the same channel and operates as an ad-hoc network. In this paper, we perform extensive evaluations using NS-2 simulations to compare PAN interconnection methods. Results show that the PAN bridge is the most useful method because it is not affected by router/node ratio and is applicable to different channel and user scenarios.