Evaluating and tracking circuit-switched telephone calls using web browsers on mobile devices

Sammanfattning: Current phone calls using the Public Switched Telephone Network (PSTN) involve costs for the enduser, provide limited call data for network operators and currently impose limitations on the type of devices that have PSTN connectability. This thesis implements and evaluates a system in which a mobile web browser connects a phone call from a smartphone to the PSTN utilizing Web Real-Time Communication (WebRTC) technology whilst maintaining sufficient audio qualityand providing a non-obtrusive user interface. The methods for this thesis included, performing a literature study, the evaluation of existing solutions and software, and the implementation of a web application prototype. The web application was successfully connected to the PSTN using preexisting software, sipML5 and Asterisk. WebSockets was used for signaling and the G.711 audio codec was used for the audio path. The ability to utilize real-time communication in a web browser proved successful. The use of real-time communication also made it possible to extract more extensive call data. Additional benefits were also noted and included, potential cost reduction for end-users, expansion of the type of devices with PSTN connectability, and the ability togather greater call data such as browser history, environments and coordinates. The user experience was evaluated by performing interviews.