Mobile location services are complex and require the integration of many disparate technologies into one seamless system. Figure 2.7 shows a sample mobile location services architecture and how the various components integrate. Central to the system is the application server, which provides the system integration framework. Services you will likely need for your mobile location services application in addition to the location server are authentication and security, user database integration, provisioning, personalization and profiling, billing, commerce, reporting, and systems management. The mobile client device communicates to the application server using the mobile network.