VoIP service demands strong QoS support for enhanced call quality and increased user satisfaction. Deploying VoIP in opportunistic communication models like cognitive radio requires thorough analysis of the factors involved in design and implementation. The objective of this paper is to implement VoIP successfully over a cognitive radio network and maintain the call quality at an acceptable lim...

This paper proposes a framework for session-level SLA (Service Level Agreement) and network-level SLA management to provide QoS-oriented application services over DiffServ/MPLS networks. DiffServ and MPLS technologies enhance the capability of QoS guarantee on IP network, and application service provider can provide QoS-oriented application services to their customers based on the transport net...

Voice over Internet Protocol (VoIP) offers a wide range of benefits to both enterprises and communications & network service providers. It provides an alternate way to make a telephone call as compared to the Public Switched Telephone Network (PSTN). The industry is slowly recognizing the potential of Voice over IP and many VOIP applications have been developed in the last ten years. This work ...

This study evaluates video codec performance over VoIP using a campus wireless network. Today, the deployment of VoIP occurs in various platforms, including VoIP over LAN, VoIP over WAN and VoIP over VPN. Therefore, this study defines which video codec provides good video quality over VoIP transmission. The soft phone is used as a medium for communication between two parties. A network manageme...

The use of Voice over Wireless Local Area Network is seeing a meteoric rise in popularity as result its simplicity, non-intrusiveness, and cheap cost implementation, well low maintenance, universal coverage, fundamental roaming capabilities. Nevertheless, deploying Internet Protocol (VoIP) (WLAN) challenging task for many network managers, architects, planners, designers, engineers. Because thi...

Wireless networks and the voice over Internet protocol (VoIP) have recently been widely adapted. VoIP services over Ad-hoc network can be accomplished by middleware embedded in mobile devices. In this study, we have implemented an intelligent VoIP system with embedded pseudo session initiation protocol (SIP) server in an Ad-hoc network. We employed the standard SIP protocol and integrated SIP p...

The VoIP networks as alternative method to traditional PSTN system has been implemented in a wide variety of structures with multiple protocols, codecs, software and hardware–based distributions. The use of cryptographic techniques let the users to have a secure communication, but the calculate throughput as well as the QoS parameters are affected according to the used algorithm. This paper ana...

The mechanisms which enable the vast majority of computer attacks are based on design and programming errors in networked applications. The growing use of voice over IP (VOIP) phone technology makes these phone applications potential targets. We present a tool to perform security testing of VOIP applications to identify security vulnerabilities which can be exploited by an attacker. Session Ini...

Voice over Internet Protocol (VoIP) has been widely used by many mobile consumer devices in IEEE 802.11 wireless local area networks (WLAN) due to its low cost and convenience. However, delays of all VoIP flows dramatically increase when network capacity is approached. Additionally, unfair traffic distribution between downlink and uplink flows in WLANs impacts the perceived VoIP quality. This p...

Voice over IP (VoIP) is the transmission of voice and multimedia content over Internet Protocol (IP) networks, this paper reviews models, frameworks and auditing standards proposed to this date to manage VoIP security through a literature review, with descriptions of both the historical and philosophical evolution reflecting an adequate knowledge of related research. Three research questions ar...