Authors: S.C. Hui, S. Foo, C.K. Yeo
Addresses: School of Applied Science, Nanyang Technological University, Nanyang, 639798, Singapore. School of Applied Science, Nanyang Technological University, Nanyang, 639798, Singapore. School of Applied Science, Nanyang Technological University, Nanyang, 639798, Singapore
Abstract: The potential of internet telephony circumventing long distance rates is certainly appealing as one can talk to someone on the other side of the world for as long as desired at no more than the cost of the local internet access and connectivity charges. This paper discusses an Internet Telephony Gateway that allows the delivery of voice services through the internet to conventional telephones on the Public Switched Telephone Network (PSTN). The gateway comprises a hardware interface card, and two software components for session and audio management. The hardware interface interacts with the trunk line to obtain audio data, answer, initiate and terminate a call. Additionally, it converts audio signal into a digital form suitable for transmission over the internet. The session and audio management interface with the internet for connection set-up, monitoring of the quality of services, negotiation of session parameters and audio communication.
Keywords: internet telephony system; internet telephony gateway; real-time voice communication; voice service; PSTN.
International Journal of Computer Applications in Technology, 1999 Vol.12 No.2/3/4/5, pp.141-150
Published online: 13 Jul 2003 *Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article