Voice over IP (VoIP) in 802.11 wireless networks (WiFi) is an attractive alternative to cellular wireless telephony. Unfortunately, VoIP traffic is well known to make inefficient use of such networks. Moreover, we demonstrate that increasing handset deployment has the potential to cripple existing hotspot and enterprise WiFi networks. In particular, our experiments show that VoIP halves the ava...

Corporate governance is generally regarded as the means by which an organization should be directed and controlled. According to good corporate governance practices, an organization should maintain a competitive advantage by securing its assets and protecting against new threats introduced through new technologies. An example of a new technology that is being increasingly implemented in organiz...

Technology makes it easier for us to communicate over a distance. However, there are still many remote areas that find difficult communicate. This is due the fact communication infrastructure in some expensive build while profit will be low. paper proposes combine voice internet protocol (VoIP) mesh network implemented on openWRT router. The routers performing functions. We set up VoIP server r...

Voice over IP (VoIP) is a promising low-cost voice communication over thewireless IP network. To provide satisfactoryVoIP services, theQuality of Service (QoS) of thewireless network should be guaranteed. This paper proposes aVoIP performance measurement freeware called NCTU VoIP Testing Tool (NCTU-VT). We compare NCTU-VT with two commercial tools SmartVoIPQoS and IxChariot in terms of packet l...

As wireless technology becomes increasingly available it only makes sense that applications like Voice over IP (VoIP) would be implemented. The merging of two areas, VoIP and wireless networks, has created Voice over WiFI (VoWiFi). Problems with VoIP are not only ported to wireless networks, they are also magnified. Mobility is an issue with wired networks, however wireless networks require mob...

VoIP speech coders have PLC mechanisms to compensate for a packet loss. In this paper, various kinds of packet losses are designed. With these losses the PLC algorithms of speech coders are evaluated and analyzed by PESQ value. Based on these outcomes, reduction of loss rate is crucial, especially for VoIP. Thus, we suggest an enhanced congestion avoidance RED mechanism to enable PLC work bette...

Resumo: O aumento do número de aplicações que geram tráfego VoIP (Voice over IP) requer que modelos adequados para este tipo de tráfego sejam empregados para um melhor dimensionamento dos recursos da rede. Neste artigo, propomos a aplicação de Misturas Gaussianas ajustadas por um algoritmo EM (Expectation − Maximization) com seleção de número de classes utilizando o princípio do Comprimento de ...

VoIP services have been considered as one of the most important services in the next generation wireless systems. VoIP service requires the same quality of service (QoS) requirement as constant bit rate services. For this reason, the IEEE 802.16 standard has defined an unsolicited grant service (UGS) to guarantee the QoS. However, the UGS is inadequate to support VoIP services with silence supp...