Voice over Internet protocol (VoIP) is one of the most important applications for the IEEE 802.11 wireless local area networks (WLANs). For network planners who are deploying VoIP over WLANs, one of the important issues is the VoIP capacity. VoIP bandwidth consumption over a WAN is one of the most important factors to consider when building a VoIP infrastructure. Failure to account for VoIP ban...

In order to improve the Voice over IP (VoIP) capacity of a Wireless Local Area Network (WLAN), we develop a relay-aided solution, which includes a relay-aided admission control scheme, a packet aggregation scheme, and a protocol for packet relay without sacrificing the voice quality. Basically, our admission control scheme utilizes relay stations to admit as many VoIP sessions as possible. When...

Voice over IP (VoIP) is the technology allowing voice and multimedia transmissions as data packets over a private or a public IP network. Thanks to the benefits that it may provide, the VoIP technology is increasingly attracting attention and interest in the industry. Actually, VoIP allows significant benefits for customers and communication services providers such as cost savings, rich media s...

Voice over IP (VoIP) is a communication technology allowing voice traffic transmission as data packets over a private or a public IP network. VoIP allows significant benefits for customers and service providers including cost savings, services integration, and systems extensibility. Nevertheless, the VoIP technology suffers from many hurdles such as architecture complexity, interoperability pro...

Voice over Internet protocol (VoIP) represents a major newish trend in telecommunications and an alternative to traditional phone systems. VoIP uses IP networks and therefore inherits their vulnerabilities. Adding voice traffic to IP networks complicates security issues and introduces a range of vulnerabilities. A VoIP system may face either an exclusive attack or an attack to the underlying IP...

Traditional Voice over Internet Protocol (VoIP) technique is based on client/server architecture. In this paper, we proposed a VoIP architecture for Ad-hoc network that provides users to communicate with each other directly through embedded pseudo SIP server. This architecture will establish a distributed VoIP system. The performance analysis of signal transmission delay will show the advantage...

Recent Voice over Internet Protocol (VoIP) technology is attracting more and more attention and interest in the industry. VoIP applications such as IP telephony systems involve sending voice transmissions as data packets over private or public IP networks as well as reassembled and decoded on the receiving side. Security concerns are always the major barrier that prevents many businesses from e...

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...