Ip Telephone Terminal, The Design And Realization

With the Internet and IP technology developing rapidly, it is realizable to transfer the real-time voice information on the Internet. The IP networks, the telecom networks and the CATV networks trend to converge at IP network. The traditional telecom networks had already stopped developing and even declined a lot. It is inevitable trend to develop the voice services on the IP networks.The rapid development of VoIP technology provides the reliable technology guarantee for the IP phone applications. The Protocols and standards of VoIP have mature completely. ITU-T H.323 standard have run to V4, and IETF SIP protocol have also run to V2.0. These protocols provide the standards for different manufacturers to develop the criterion IP phone products. The development of the embedded technology, especially the appearance of a great deal of low price, high performance embedded chips, provide rich hardware resource for IP phone development and production.This paper is based on a successful implementation of a H.323 IP phone terminal, which was realized by the project team that the author participated in. In this paper, the author analyzes the H.323 protocol stack at first, then presents a detailed H.323 terminal system design and implementation solution on the SCM developing platform of PalmMicro. The platform is based on Pal 688 which is a high performance, low price, VoIP SoC chip. In the end, the author sets forth the test result and ideas for future improvement.