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There are certain aspects in the field of networking that needs to be accomplished, yet it is very difficult to achieve. One such concept is Optimization. Achieving a high degree of reliability will eventually lead us to Optimization. But, achieving high degree of reliability?? This indeed is a very big problem that needs a solution. There have been many solutions before that solves the problem in...
The primary role of network access control is to decide on the validity of user's identity accepted into the networks and authorization accessed to the particular resource so that users conforming to their established access polices achieve predefined services. This paper presents a specific scenario which supports quality of service (QoS) in network domain. The QoS access rules are based not only...
In a downlink orthogonal frequency division multiple access (OFDMA) system, allocating sub-channels and power across multi-user can require excessive feedback of channel state information. An efficient proportional fair scheduling algorithm based on cluster feedback scheme is proposed in the paper. Simulation results show that the scheme needs only little feedback information while maintaining guaranteed...
Data mining and scoring tool providers require users to use provider-specific ways to invoke their services. The provider-specific approach could be a major factor affecting why data mining tools and applications are not currently as widespread as one might hope. However, SOA can implements the loose coupling between the services provider and services consumer. Using Web service protocol (such as...
Rich media application enables plenty of interactive, information-rich services to enhance end user's viewing experience. In current standards released for such service, only one rendering space is defined to handle multiple types of content belonging to the same service. However, a new trend is to assign more than one terminal device to render rich media application in a cooperative way inside a...
Unlike traditional routing schemes that route all traffic along a single path, multipath routing strategies split the traffic among several paths in order to ease congestion. It has been widely recognized that multipath routing can be fundamentally more efficient than the traditional approach of routing along single paths. aiming at the increasing network traffic and the deficity that the former Ant...
This paper focuses on the rate-distortion optimization of low-delay 3D video communications based on the latest H.264/MVC video coding standard. The first part of the work proposes a new low-complexity model for distortion estimation suitable for low-delay stereoscopic video communication scenarios such as 3D videoconferencing. The distortion introduced by the loss of a given frame is investigated...
Our work focuses on selecting a trusted service from service consumer's perspective. First, we distinguish the two kinds of trust context to separate the ability of service as both a service provider and a service consumer in a service web; and we classify the reputation into two different categories. Second we generate a reputation metric model by improving Subject Logic. The trust decision model...
Take a research in depth on the modeling problem of service path selection based on SON. Firstly, the optimal model is built with the optimal goal of balanced loading and with the functional constraints of users for composed service and multi-QoS constraints. Then the layered method and improved Ant algorithm are adopted to solve this problem. Finally, a simulated emulation is made to the algorithm,...
In this paper, we investigate the spectrum scheduling problem for next generation multiband orthogonal frequency division multiplexing (MB-OFDM) ultra-wideband (UWB) systems under QoS and interference constraints. Based on a constrained optimization problem formulation, we propose a cross-layer scheduling solution that takes into account the unlicensed UWB users channel and QoS conditions as well...
Many new broadband, emerging applications such as high definition 3D video streaming or on-line gaming are going to be part of the future home. Current home networks are still not capable to cope with the tight requirements asked by these kind of applications. Moreover, many underlying wired and wireless transmission technologies are available, but no solution to reach a convergent framework is available...
Fourth Generation Networks will invariably adopt MIMO-OFDMA techniques, in order to cope with increased data rate demands and improved Quality of Service (QoS) requirements. OFDMA is a popular multiple access candidate, since it facilitates multi-user diversity by enabling two dimensional multiple access, in time and frequency domains. Random Beamforming enables exploitation of spatial multi-user...
Future wireless access will involve a variety of integrated and interworking technologies. Depending on the conditions (e.g., the specific application, the quality of service requirements, the user mobility) each session will be served through the most suited access network; following some event, there will be a variation of the access technology, which is called vertical handover. Although the use...
In new generation cellular networks, opportunistic schedulers take advantage from the delay-tolerance of data applications to ensure that transmission occurs when radio channel conditions are most favourable. “Proportional Fair” (PF) is a well-known opportunistic scheduler that provides a good compromise between fairness and efficiency when transmitting long flows. Unfortunately, the PF algorithm...
Block diagonalization is a linear precoding technique which eliminates the multi-user interference at the transmitter side by creating parallel orthogonal single user links. In this technique, the transmit diversity order is fixed for each user and only power can be controlled to satisfy SINR requirements. This restricts the degrees of freedom available for resource allocation and limits the energy...
The media richness of the services available to the end consumer has had a constant increase rate over the last century. This leads nowadays to the need of Ultra Broadband at home to handle future services such as 3D video that may reach the Gigabit per second. Moreover, beyond the bandwidth increase, the home network capabilities have to evolve in order to support new usages and to guarantee Quality...
In this paper, we propose a novel channel selection algorithm for a cognitive radio system that coexists with legacy wireless LAN systems operating in the ISM bands. The cognitive system is capable of scanning its environment to measure ISM channel occupancy in terms of WLAN channel utilization. The system takes the opportunity of spectrum availability to facilitate its communication to the cognitive...
HSDPA (High Speed Downlink Packet Access) is drawing great attention as the 3.5G technology capable of providing higher data rate packet switch services over Universal Mobile Telecommunication System (UMTS) to support broadband services like multimedia conferencing, VoIP, or high-speed internet access. The paper proposes the use of a Learning Vector Quantization (LVQ) Neural Network able to estimate...
Many duty cycling MAC protocols exploit preamble sampling technique to improve the energy efficiency. In this technique, all the devices periodically listen to the medium for a short duration and then go back to sleep if medium is found idle. When a device wants to send data it transmits a long preamble followed by data bits. When the receiver wakes up and detects the preamble it stays awake until...
Due to the license-exempt nature of the cognitive radio (CR), multiple CR networks may operate (coexist) on the same channel. In this paper, we first discuss some techniques for self-coexistence of CR local and personal area networks, where the self-coexistence means the coexistence of homogeneous CR networks using the same PHY/MAC protocol. Then, we propose a self-coexistence etiquette for the ECMA...
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