RSSI stands for Received Signal Strength Indicator and describes a method for calculating the position with the help of BLE signals. The term beaconing is also used similarly. RSSI is the standard positioning method in many IPS and RTLS. With RSSI, accuracies of 1 to 3 meters are achieved. For this accuracy the term ” room accuracy” is also used analogously. The method is sufficient to even realize indoor navigation in buildings.