Development of (VOIP) applications for mobile devices

• Main Author: Lee, Heng Leong.
• Other Authors: Lau Chiew Tong
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Wireless communication systems
• Online Access: http://hdl.handle.net/10356/17041
• Institution: Nanyang Technological University

In Singapore, mobile phones have achieved almost complete market penetration. Most of the mobile phones equipped with WiFi functions enable user to access the Internet. Majority usage of the Internet by mobile phone users are for general purpose like web surfing and checking emails. To make better use of the Internet, phone calls can be made without incurring additional cost. In this project, Voice over Internet Protocol (VOIP) Program software is proposed to enable user to make free phone call via the Internet. In order to develop the VOIP Program software, some research on VOIP has been undertaken. Previous knowledge and components needed to develop the software were noted and taken into consideration in the design of the system. At the same time, Session Initialization Protocol (SIP) Registrar Server is also designed to resolve the IP address issues that were faced by VOIP Program. With keeping the objective in mind, VOIP Program is designed to make phone calls using the popular SIP protocol. SIP is a signaling protocol for establishing real-time calls over IP networks. To enhance its functionality, VOIP Program comes with other features. The features include sending, receiving message and storing contacts in the address book. SIP Registrar Server is used to store the user location. As the IP Address changes due to the changes of user location, the registrar server will be responsible for storing the user latest IP address. In order to increase the usage efficiency, additional user information is stored in the registrar server to allow the VOIP Program to expand its function capabilities.