WiFi Location technology rely purely on mobile devices sending RSSI/Location
information, based on pure probe request messaging, to the Access Points (AP).
The information is sent on most channels and received by neighbor APs on
different channels, which is good for location estimation.
Device probing frequency is
reducing; updates vary from 10 seconds to 5 minutes depending on client, OS, driver,
battery, current, and client activity. This results in inadequate data points to
represent real-world movement.
FastLocate, we add the capability to get RSSI/Location information using data
packets received by the AP for higher location refresh rates. Using data
packet, Location Based Services (LBS) updates are initiated by the network and
are available more frequently. This provides more data points to accurately
represent end user activity. While it is tempting to think of capturing RSSI
from data packets as an incremental improvement over capturing RSSI from probe
frames, it is actually a significant step forward. When WiFi mobile devices
connect to the AP, neighboring APs are unable to hear the data packets because
they are on different channel. This is bad for location estimation. FastLocate
technology uses Cisco’s modular APs, 3600 and 3700, with Wireless Security
Module (WSM). WSM in the associated AP and the neighboring APs scan channels at
the same time to get multiple RSSI readings from a data packet transmission and
thus locate the mobile device. This can occur without taxing the data serving
radios and no performance hit to the data service on the serving radios in
2.4-GHz and 5-GHz band.
on data packets makes the location more consistent across devices. This also
works with iOS8 implementations, where a device may randomize their MAC address
in probe frames.
Figure 1. The Real impact:
More Granular LBS data for business critical information