Our customer, a Tier-1 carrier in Western Europe recently launched Voice over LTE (VoLTE) and Voice over Wi-Fi (VoWLAN) services. For public health and safety purposes, local regulation mandates any wireless service provider to identify and transmit the user’s current location whenever an emergency call is made over one of these channels. This information serves to route the call to the closest public safety answering point and to provide the relevant location data. As the VoLTE and VoWLAN are using IMS core-network, the traditional emergency call location platforms (based on 2G/3G circuit-switch technology) cannot be used to locate emergency IP-calls.


Whereas fall-back solutions on 3G networks can be set-up as temporary workarounds, they are useless for indoor location calls over Wi-Fi under no cellular coverage. Locating those VoWi-Fi calls securely in 100% cases represents a real challenge in the current state of standards. Additionally mobile operators do not control the location accuracy of those Wi-Fi access points they don't manage.

Solution and Results

Intersec passive location technology automatically retrieves access point identification of all handsets connecting to VoWLAN and looks-up for their corresponding location on a Wi-Fi access point location database. On the fly, the solution ensures their consistency, leveraging on the mobile network cell cartography. The operator therefore benefits from an emergency call solution fully compliant with local regulation, that provides trusted and reliable location for all emergency calls in any situation.