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This research evaluated the cyber security effectiveness of the intrusion prevention system for Voice over Internet Protocol (VoIP) focusing on the defense of Denial of Service (DoS) which propose to disturb server providing VoIP services. This will give a strong impact on entrepreneurs. Intrusion prevention system (IPS) has been employed based on Snort software, this study as a preventive technique...
To improve the user-perceived quality of service (QoS) performance of voice over Internet protocol (VoIP) services, a retransmission of a packet experienced an error is needed in broadband wireless access networks. This means that the number of wireless resources to successfully transmit a packet can be increased by the retransmitted packet. For this reason, there can be a trade-off between the QoS...
Network planning presents a number of difficulties and risks but performed in an optimal way may turn beneficial. In this work we address a new way of achieving optimal network planning for Voice over IP (VoIP) services by using historical data to profile service usage. We show how to obtain a sound set of service use clusters based on calling behaviours by applying a Simple Expectation Maximisation...
Realtime voice communication is an essential requirement in emergency scenarios. Mobile ad hoc network (MANET) is a best suitable option for premises like conference or convention centre. The performance of VoIP services depends on voice encoder scheme. In this paper, the performance of different voice codec i.e.G.728, G.711, G.723, G.729, G.726, GSM-EFR, GSM-HR under similar load condition for Interactive...
Existing uplink scheduling schemes at subscriber station (SS) in WiMAX suffer from problems like waste of resources and greater access delay for VoIP services. We propose an efficient uplink scheduling scheme to solve above mentioned problems. The SS uses two reserved bits of generic MAC header of IEEE 802.16d to record the voice status of current time unit and informs the base station (BS) without...
Integrating voice / video communication into business processes can accelerate resolution time, reduce mistakes, and establish a full audit-trail of the interactions. Some VoIP service providers offer website based or plugin based solutions, which are, however, difficult to integrate with other applications. A promising approach to overcome these disadvantages is the development of appropriate Web...
Motivated by the rapid increase of VoIP services with G.711 for telephone speech, a new ITU-T recommendation, G.711.0 (frame-wise stateless lossless compression scheme for G.711 log PCM symbols), has been standardized. The standard scheme has several coding parts, each of which is adaptively selected depending on the characteristics of the input. Among them, the mapped domain prediction part is the...
In recent years the Department of Defense has aggressively invested in development of an Internet Protocol (IP) based network that interconnects mobile air platforms and ultimately will also connect to the Global Information Grid (GIG) as part of its Net-Centric Warfare initiatives. One of the major visions for the IP based networks is to support interoperable voice communication amongst heterogeneous...
This paper has evaluated the system performance for the voice over Internet protocol (VoIP) services supported by the IEEE 802.16 systems in terms of the packet loss and delay, and it has also calculated the mean opinion score (MOS) in order to estimate the user's satisfaction for the VoIP services. By the simulation results, the MOS of the VoIP service supported by the unsolicited grant service (UGS)...
This work gives an overview of SIP-Trunking solution and explains the existing difficulties in implementing VoIP services, when this architecture is deployed in multivendor environment. The causes of these problems are explained with two existing approaches used by carrier to solve interoperability: they are Full Jacket SIP-Trunk and Customized SIP-Trunk. A solution to cover the lackings of SIP standards...
Whilst SAML-based federations are most often used by academic and semi-commercial institutions that focus only on attribute-based authentication, we foresee a growing interest for service providers providing charged services. Since more and more academic and semi-commercial federation participants offer Voice-over-IP (VoIP) services, this type of service provides an entry point into identity federation...
This paper presents a Cross-Layer scheme that tries to improve the performance of real-time traffic over TCP in 802.11e wireless networks. It is based on a well-known TCP-friendly, binomial algorithm at the Transport layer, which is jointly configured with the 802.11e protocol at the MAC layer. TCP-friendly schemes have shown to improve the quality of media transfer over wired and wireless networks...
Given limited network resources, applications, particularly those that support real-time services, must deliver an ambient quality-guaranteed service. Different applications are associated with different Quality of Service (QoS) concerns, as well as different QoS control parameters. This work discusses the QoS specifications of three wireless access technologies, 3G, WiMAX and WiFi, in the design...
The next-generation backbone routers need large-bandwidth communication capability because of increased future Voice over Internet Protocol (VoIP) services. Providing these or other future ubiquitous services will require new Network Processor (NP) designs, since these protocols or services are expected to require enormous increases in processing power in order to address their fine-grain communication...
The dominance of multimedia applications has increased with the emergence of high speed data networks. Among the multimedia applications, VoIP has placed itself in a strong position. However, the market is dominated by a number of VoIP applications with different architectural and protocol layouts. Therefore, analysis and comparison is necessary to understand their behavior and to define the QoS of...
This paper introduces the system concept and specifications for an enhanced version of the Wireless IP Access System (WIPAS), the Advanced WIPAS, which is a fixed wireless access (FWA) system that provides higher speed and real-time communication for triple play services: broadband IP service, 4class Quality of Service (QoS) especially VoIP services, and multicast HDTV video transmission services...
IEEE 802.16 is a promising technology in broadband wireless access area. In this paper, a novel performance analysis model is provided focusing on the VoIP services in TDD OFDMA-based IEEE 802.16 system. Based on the analysis results, a united packet aggregation scheme for both uplink and downlink is provided. The simulation results show that the packet aggregation in MAC layer not only improves the...
In IEEE 802.16e OFDMA system, the system capacity for accommodating VoIP traffic with small-sized PDUs is severely reduced due to a large amount of signalling overhead. In order to mitigate this problem, the IEEE 802.16 maintenance group has recently proposed a persistent allocation scheme to increase the voice over IP (VoIP) system capacity. However, it is difficult to use the conventional modulation...
Voice over Internet protocol (VoIP) is a prevalent multimedia application nowadays. For mobile nodes (MNs) using VoIP services in wireless networks, the handoff issues need to be taken into account. Stream control transmission protocol (SCTP) is a potential transport layer protocol with multi-homing and multi-streaming functions. Mobile SCTP with dynamic address reconfiguration (DAR) extends SCTP...
Forthcoming next generation networks (NGNs) introduce a new trend of integration into one all-IP platform. This process will decouple VoIP services from the network providers, introducing new service distribution aspects. VoIP devices will be enabled to seamlessly switch between wideband and narrowband speech operators and roam across diverse networks on demand, even during active calls. To design...
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