Generating location information for an e911 call

A system, comprising:

• a memory;
• and
• at least one device configured to:
• receive a session initiation protocol (SIP) Invite message associated with a Voice over WiFi (VoWiFi) call made by a user device,
• determine if the SIP Invite message includes location information associated with the user device,
• in response to determining that the SIP Invite message includes location information associated with the user device, initiate a location session with the user device,
• generate assistance data based on the location information, wherein the assistance data is to be used by the user device to generate assisted global positioning system (aGPS) measurements,
• transmit, to the user device and during the location session, the assistance data,
• receive, from the user device, aGPS measurements based on the assistance data, and
• determine, based on the aGPS measurements, a location of the user device.

A non-transitory computer-readable medium having stored thereon sequences of instructions which, when executed by at least one processor, cause the at least one processor to:

• receive a session initiation protocol (SIP) Invite message associated with a Voice over WiFi (VoWiFi) call made by a user device;
• determine if SIP Invite message includes location information associated with the user device;
• in response to determining that the SIP Invite message includes location information associated with the user device, initiate a location session with the user device;
• generate assistance data based on the location information, wherein the assistance data is to be used by the user device to generate assisted global positioning system (aGPS) measurements;
• transmit, to the user device and during the location session, the assistance data;
• receive, from the user device, aGPS measurements based on the assistance data;
• and
• determine, based on the aGPS measurements, a location of the user device.