A system for determining a location associated with a mobile device in a IP- based wireless telecommunications network, the mobile device being communicatively coupled to the IP-based wireless telecommunications network via an access point, the system comprising: a network controller that is arranged to identify data associated with the mobile device, the identified data including a MAC address associated with the access point and an IP address associated with the access point; a location database that is arranged in communication with the network controller, wherein the location database is arranged for indexing with the identified data associated with the mobile device, wherein the location database comprises values associated with a location identifier associated with the MAC address, a serving area of the IP address associated with the access point, and an uncertainty rating associated with each of the above locations; wherein the network controller is further configured to: receive a positioning request message from a serving mobile location center of the system; communicate a location request message to the location database, wherein the location request message identifies the MAC address associated with the access point associated with the mobile device and the IP address associated with the access point; receive a reply from the location database in response to the location request message, wherein the reply includes location information associated with the mobile device, the location information including the location identifier associated with the MAC address and/or the serving area of the IP address associated with the access point, and the uncertainty rating associated with each included piece of location information; communicate a positioning response message to the serving mobile location center, wherein the positioning response message identifies the location information included in the reply from the location database; and receive from the serving mobile location center a location estimate including a latitude estimate and a longitude estimate and an uncertainty rating associated with the location estimate, the location estimate being calculated using the location information identified in the positioning response message. a network controller that is arranged to identify data associated with the mobile device, the identified data including a MAC address associated with the access point and an IP address associated with the access point; a location database that is arranged in communication with the network controller, wherein the location database is arranged for indexing with the identified data associated with the mobile device, wherein the location database comprises values associated with a location identifier associated with the MAC address, a serving area of the IP address associated with the access point, and an uncertainty rating associated with each of the above locations; wherein the network controller is further configured to: receive a positioning request message from a serving mobile location center of the system; communicate a location request message to the location database, wherein the location request message identifies the MAC address associated with the access point associated with the mobile device and the IP address associated with the access point; receive a reply from the location database in response to the location request message, wherein the reply includes location information associated with the mobile device, the location information including the location identifier associated with the MAC address and/or the serving area of the IP address associated with the access point, and the uncertainty rating associated with each included piece of location information; communicate a positioning response message to the serving mobile location center, wherein the positioning response message identifies the location information included in the reply from the location database; and receive from the serving mobile location center a location estimate including a latitude estimate and a longitude estimate and an uncertainty rating associated with the location estimate, the location estimate being calculated using the location information identified in the positioning response message. receive a positioning request message from a serving mobile location center of the system; communicate a location request message to the location database, wherein the location request message identifies the MAC address associated with the access point associated with the mobile device and the IP address associated with the access point; receive a reply from the location database in response to the location request message, wherein the reply includes location information associated with the mobile device, the location information including the location identifier associated with the MAC address and/or the serving area of the IP address associated with the access point, and the uncertainty rating associated with each included piece of location information; communicate a positioning response message to the serving mobile location center, wherein the positioning response message identifies the location information included in the reply from the location database; and receive from the serving mobile location center a location estimate including a latitude estimate and a longitude estimate and an uncertainty rating associated with the location estimate, the location estimate being calculated using the location information identified in the positioning response message.