International Journal of Computer Networks and Applications

Wen-Shiung Chen ¹, Lili Hsieh ², Ying-Neng Hsieh ¹

Affiliations
1 Dept. of Electrical Engineering, National Chi Nan University, Nan-Tou, TW
2 Dept. of Information Management, Hsiuping University of Science and Technology, Taichung, TW

Abstract

Push-to-Talk (PTT) is a service that allows users using mobile phones in a way like walkie-talkie. All big telecommunication vendors and operators consider PTT an emerging application. 3GPP and OMA regulate the PTT specifications on the basis of Session Initiation Protocol (SIP) to assure interoperability. However, current PTT services are dedicated to cellular phones. We would like to realize PTT services with popular 802.11 wireless networks and VoIP services. Thus, in this paper, we implement a PTT system that works in 802.11 networks. Moreover, we interconnect it with GPRS network to compare the performance in-between these two heterogeneous networks. Simulation result shows that the latency to hear the talk calling from GPRS network to 802.11g network is only about 1~2 seconds while that of from 802.11g network to GPRS network is 6 seconds.

Keywords

Push-to-Talk (PTT), Session Initiation Protocol (SIP), Wi-Fi Network, 802.11.

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Heng-Te Chu ¹, Lili Hsieh ², Wen-Shiung Chen ³

Affiliations
1 Dept. of Information Networking Technology, Hsiuping University of Science and Technology, Taichung, TW
2 Dept. of Information Management, Hsiuping University of Science and Technology, Taichung, TW
3 Dept. of Electrical Engineering, National Chi Nan University, Pui, Nantou, TW

Abstract

Instant messaging (IM) services have grown dramatically in recent years. In telephone networks, short message service keeps dominating mobile data services. As the rise of nomadic need, to bridge both messaging services is becoming a promising niche. In this paper we propose an infrastructure, based on the XML-based protocol, XMPP, to simplify the interconnections and enable the legacy handsets for instant message service. Although there is another competitive approach, SIMPLE, based on SIP, we will analyze how the XMPP is to outdo SIMPLE.

Keywords

Instant Messaging (IM), Short Message Service (SMS), XML, XMPP, SIP, SIMPLE.

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