Novel Method of Improving Quality of Service for Voice over Internet Protocol Traffic in Mobile Ad Hoc Networks In recent years, the application of Mobile Adhoc Network (MANET) with Voice over Internet Protocol (VoIP) has been increased.xc2xa0 However, the level ofxc2xa0Quality of Service (QoS) for VoIP traffic in MANET, while there is no infrastructure, will reduce when dealing with a large number of calls. In this type ofxc2xa0dynamic environment, the developing ofxc2xa0a new infrastructure becomes more costly and timeconsuming. In this paper, we proposed an efficient method, called the Quality of ServiceNearest Neighborxc2xa0(QoSNN), to improve the QoS level for VoIP in order to manage the huge number of calls over MANET network. We utilized the Adhoc Ondemand Distance Vector (AODV) protocol as the underlying routing protocol to implement our proposed method. We evaluated the proposed QoSNN method using Network Simulator version 2 (NS2). The performance of the proposed QoSNN method was compared with Lexicographic orderxc2xa0method. The comparison was evaluated in terms of  R factor, endtoend delay, packet loss ratio, and packet delivery ratio performance metrics. In addition, the proposed method evaluated under different network parameters such as VoIP CODECs, node mobility speed,xc2xa0number of calls and number of nodes. The comparison results indicate that the proposed QoSNN outperform the Lexicographic order       method.

Handover Algorithm for Video Communications by Sharing Communication Quality Information of Access Points between Terminals In recent years, the demand for multimedia services that can handle voice andor videos on mobile terminals has increased. Many handover algorithms have been proposed for switching the connection between different networks while maintaining QoE (Quality of Experience), which is a metric that is a measure of usersxe2x80x99 satisfaction when using a certain service or application. The QoEdriven VHO algorithm is one of such algorithms using a prediction model of QoE for movies streamed over wireless networks. Since the algorithm may not provide an acceptable level of quality when network performance temporarily decreases, the authors also proposed an algorithm (hereinafter referred to as the xe2x80x9cprevious algorithmxe2x80x9d) to improve the problem. However, since these algorithms cannot predict QoE of candidate networks before switching, the connection may be switched to a network with much lower QoE. In order to solve the problem, this paper proposes a new handover algorithm for video communications by sharing communication quality information of access points between terminals. In this algorithm, each mobile terminal creates a list specifying the communication quality of the connected access point and shares it with other terminals. The simulation results show that terminals in the proposed method can connect to the access points with better QoE for longer durations than the QoEdriven VHO algorithm and the previous algorithm.