Exam 300-425 topic 1 question 199 discussion

Guide: Location uses trilateration, which means that you need several APs around each point of your floor so that a location engine in the infrastructure can combine the signal these APs receive from each client and compute the client location. For each point of the floor, you need at least three surrounding APs.

tricky question , when a question is asking about -75dB client RSSI from X APs? the answer is 3 APs. But here the question is asking about design and placement then based on cisco recommendation we should try to stagger the APs and having 4 APs in each floor

Basic Rule: Deploy minimum of 4 APs per floor https://www.cisco.com/c/en/us/td/docs/wireless/controller/technotes/8-8/b_ap_4800_hyperlocation_deployment_guide.html#id_81793

Minimum detected received signal thresholds—For mobile devices to be tracked properly, it is highly recommended that access points report mobile device RSSI to their respective controllers at levels meeting or exceeding the RSSI cutoff value that is configured in WCS. A minimum of three access points (and preferably four or more for optimum accuracy) should be reporting this level of signal strength or better for any device being localized. Mobile device RSSI reported below this level may be discarded by the location appliance. https://www.cisco.com/en/US/docs/solutions/Enterprise/Mobility/emob30dg/Locatn.html

Location services require 3-4 APs. Here, the network must be “location-ready” so 3 APs/flr should be considered.

for a better accuracy location services, each device needs to be seen by at least 4 AP's

C is correct