VoIP isn’t secure since it uses the Internet to which many people connect simultaneously. In this paper, we designed and implemented a Wireless VoIP + VPN system with which secure telephone calls are possible using the open project SIP VoIP Gateway, 'Asterisk' and 'OpenVPN'. Key-Words: VoIP, VPN, SIP, Wireless, Security, WiFi

Voice over Internet Protocol (VoIP) is a way to carry out a telephonic conversation over a data network. VoIP applications, with SIP and RTP, promise converged telecommunications and data services that are cheaper, more versatile and provide good voice quality as compared to traditional offerings. Although VoIP is widely used, VoIP on mobile devices is still in its infancy. Currently, there are...

These days a massive deployment of VoIP is taking place over IP networks. VoIP deployment is a challenging task for network researchers and engineers. This paper presents a detailed simulation approach for deploying VoIP successfully. The simulation uses the OPNET network simulator. Recently OPNET has gained a considerable popularity in both academia and industry, but there is no formal or know...

Owing to the enormous growth of VoIP applications, an effective means of identifying VoIP is now essential for managing a number of network traffic issues, such as reserving bandwidth for VoIP traffic, assigning high priority for VoIP flows, or blocking VoIP calls to certain destinations. Because the protocols, port numbers, and codecs used by VoIP services are shifting toward proprietary, encr...

Voice over internet protocol (VoIP) is a method of providing phone services over dedicated public IP networks. It allows significant cost savings over traditional Public Switched Telephone Networks (PSTN). Speech quality, as perceived by the users of VoIP telephony, is critically important. Signal quality of the VoIP system is degraded by various network layer problems, which include delay, pac...

Voice over IP (VoIP) is a key driver in the evolution of voice communications, and the high transmission rate property of High Speed Packet Access (HSPA) is expected to satisfy the strict delay requirements of VoIP. Therefore, the aim of this paper is to evaluate the performance of VoIP service in HSPA network. This paper presents a mathematical model for VoIP capacity in HSPA under the constra...

In this research, we propose to implement Secure Real Time Transport Protocol (SRTP) on VoIP services in campus environment. Today, the deployment of VoIP in campus environment over wireless local area network (WLAN) is not considered on security during communication between two parties. Therefore, this study is to analyzed SRTP performance on different VoIP codec selection over wired. We have ...

In this thesis, we focus on large scale Voice over IP (VoIP) deployment over heterogeneous Internet environments. We first present an overview of VoIP coding and transmission mechanisms. Then, we investigate performance limitations in the case of a large number of VoIP flows transported over wired Internet links between peer VoIP gateways. We address, in the first part of the thesis, the need t...

Insufficient Quality of Service (QoS) of Voice over Internet Protocol (VoIP) is a growing concern that has lead the need for research and study. In this paper we investigate the performance of VoIP and the impact of resource limitations on the performance of Access Networks. The impact of VoIP performance in Access Networks is particularly important in regions where Internet resources are limit...

VoIP (Voice over Internet Protocol) is a growing technology during last decade. It provides the audio, video streaming facility on successful implementation in the network. However, it provides the text transport facility over the network. Due to implementation of it the cost effective solution, it can be developed for the intercommunication among the employees of a prestigious organization. Th...