Performance assessment of VoIP service over different handover mechanisms in UMTS networks

Many researchers have discussed various topics in universal mobile telecommunication system (UMTS) networks: the process of switching from one cell to another for the subscriber and the impact of the quality of the connection during the transition process, quality of services (QoS), the quality of the uplink and downlink carrier line, the various types of code for the voice transmitted through the Internet, especially the research that discussed voice over internet protocol (VoIP) technology as voice travels from cell to cell in mobile networks, depending on the type of delivery. In this paper, a proposed scenario of a UMTS network was implemented to evaluate the multicellular VoIP movement; the proposed UMTS network was simulated using the OPNET 14.5 simulator. The calculation and analysis of the different parameters of the user while moving from one cell to another with different movement speeds considered, the best mean opinion score (MOS) value (3.19) registered for the scenario (soft handover) comparing with another type of handover (3.00)

Analyzing of MOS and Codec Selection for Voice over IP Technology

In this research, we propose an architectural solution to implement the voice over IP (VoIP) service in campus environment network. Voice over IP (VoIP) technology has become a discussion issue for this time being. Today, the deployment of this technology on an organization truly can give a great financial benefit over traditional telephony. Therefore, this study is to analyze the VoIP Codec selection and investigate the Mean Opinion Score (MOS) performance areas evolved with the quality of service delivered by soft phone and IP phone. This study focuses on quality of voice prediction such as i) accuracy of MOS between automated system and human perception and ii) different types of codec performance measurement via human perception using MOS technique. In this study, network management system (NMS) is used to monitor and capture the performance of VoIP in campus environment. In addition, the most apparent of implementing soft phone and IP phone in campus environment is to define the best codec selection that can be used in operational environment. Based on the finding result, the MOS measurement through automated and manual system is able to predict and evaluate VoIP performance. In addition, based on manual MOS measurement, VoIP conversations over LAN contribute more reliability and availability performance compare to WAN.Comment: 14 pages, exposed on 5th International Conference "Actualities and Perspectives on Hardware and Software" - APHS2009, Timisoara, Romani

A Survey on Enhancing the QoS through voice Quality for Voice over Wireless LANs (VoWLAN)

Voice over Internet Protocol (VoIP) is one of the important technologies that allow voice transmission over the IP network. Various voice codec are available for VoIP as this is a rapidly changing technology. It can be an effective renewal for the traditional telephone systems (PSTN) because of extreme utilization of its sources as well as to provide very low cost. Apart from, Wireless Local Area Network (WLAN) has become apparent as a durable networking technology. Hence, the combination of these two popular technologies is growing so fast all over the world. Voice over WLAN will be a tool to provide low-cost and reliable voice services on wireless media. However just like other wireless applications, VoWLAN has also faced few challenges that need to be considered. Quality of Service (QoS) is one of the primary requirements in different kind of wireless applications. In this survey some of the important QoS requirement (latency, delay, jitter etc) have been analyzed, and it also has the introspection of the E- model and MOS (Mean Opinion Score) value for voice quality while using of different ITU-T codec. Therefore it makes Voice over WLAN a challenging research topic. In this study we will address all VoWLAN issues. DOI: 10.17762/ijritcc2321-8169.150516

Simulation Study on Deployment of VoIP on Wireline Network

Voice over Internet Protocol is a revolutionary technology which has become a key topic in both the growing Internet industry and established telecommunications industry. VoIP has become a potential alternative to the Public switching telecommunication network due to its reduced cost. However, despite its reduced cost it has so many challenges which affect its successful deployment. This paper presents a detailed simulation approach for deploying VoIP successfully using the OPNET network simulator. The approach and work presented in this paper predict, prior to the deployment of VoIP equipment  the number of VoIP calls that can be sustained by an existing network while satisfying  quality of service requirements of all network services and leaving adequate capacity for future growth. This is achieved by carrying out a number of simulations on a segmented network, which provided graphical results used in the study of VoIP traffic and other major devices. These results will benefit network planners in the successful implementation of VOIP services