today, optimal performance and cost advantages of using internet telephony are obvious. despite current standardized techniques, voice transferring through protocol (voip) has lower security than traditional telephony. one of the most important security issues which should be noticed in using voip is end -to-end user2 identity, i.e. when  there is a connection between user a and b, user a shoul...

Supporting as many Voice-over-IP (VoIP) users as possible in a Broadband Wireless Access network using limited radio resources is a critical issue. However, performance of VoIP services is affected by several parameters defined in the IEEE 802.16e protocol. In this paper we developed a theoretical model and an algorithm to evaluate the performance of some of the most important VoIP codecs. Simu...

This paper analyzes the future evolution paths of voice communications services. The focus is on defining the role and success potential of different types of VoIP services, ranging from IM-like doit-yourself VoIP to operator-managed VoIP services with QoS guarantees and PSTN interconnectivity. The paper proposes a simple model for voice service classification, and analyzes the end-user value a...

Voice over Internet Protocol (VoIP) is a form of voice communication that uses audio data to transmit voice signals to the end user. VoIP is one of the most important technologies in the World of communication. Around, 20 years of research on VoIP, some problems of VoIP are still remaining. During the past decade and with growing of wireless technologies, we have seen that many papers turn thei...

As VoIP telecommunication networks are becoming popular, more and more VoIP calls are being madeto accomplish security critical activities, e.g., E911 services, phone banking. However, the security ram-ifications of using VoIP have not been fully recognized, and there exists a substantial gap in the under-standing of the potential impact of VoIP exploits on the VoIP users. In this c...

Voice over IP (VoIP) is the technology allowing voice traffic transmission as data packets over a private or a public IP network. VoIP allows significant benefits for customers and communication services providers. The main are cost savings, rich media service, phone and service portability and mobility, and the integration with other applications. Nevertheless, the deployment of the VoIP techn...

Since the inception of telephony, the public switch telephone network (PSTN) has had major impact in everyday life. The widespread adoption of VoIP has totally revolutionized the telephony industry. With many free services for the users, VoIP is favored over the traditional PSTN. A major concern for VoIP is voice quality, as it is a network-based packet switching technology. VoIP will come in h...

In a recent year usage of VoIP subscription has increased tremendously as compare to Public Switching Telephone System(PSTN). A VoIP subscriber would like to know the exact tariffs of the calls made using VoIP. As the usage increases, the rate of fraud is also increases, causing users complain about excess billing. This in turn hampers the growth of VoIP .This paper describe the common frauds a...

Abstract To determine the optimal network architecture between Basic Service Set, Extended Set and Independent this study established a new algorithm to assess Voice over Internet Protocol (VoIP) metrics of different IEEE 802.11 technologies. An important coefficient for each VoIP metric parameter has been invented rank standards identify most efficient one application. The best overall perform...

This article concentrates in the issues of network dimensioning for voice over IP (VoIP). The network under dimensioning is an IP network between VoIP user devices. First, a short introduction to VoIP in general is given. Second, the issues in network dimensioning for VoIP are identified. Third, bandwidth requirements of VoIP are calculated. Fourth, basic approaches to Quality of Service are di...