626 research outputs found
Enhanced cell visiting probability for QoS provisioning in mobile multimedia communications
This paper presents an enhanced cell visiting probability (CVP) estimation technique by integrating both mobility parameters such as position, direction, and speed together with exponential call duration probability of mobile units. These improved CVP estimates can be used in both adaptive and nonadaptive mobile networks to enhance QoS parameters. This paper also presents a new shadow-clustering scheme based on these enhanced CVPs, which is then applied to the call admission control scheme similar to the one, called predictive mobility support QoS provisioning scheme, proposed by Aljadhai and Znati (2001). Simulation results confirm that this new shadow-clustering scheme outperforms predictive mobility support QoS provisioning scheme in terms of different QoS parameters under various different traffic conditions
A Review on Provisioning Quality of Service of Wireless Telemedicine for E-Health Services
In general, on-line medical consultation reduces time required for medical consultation induces
improvement in the quality and efficiency of healthcare services. All major types of current e-health applications such as ECG, X-ray, video, diagnosis images and other common applications have been included in the scope of the study. In addition, the provision of Quality of Service (QoS) for the application of specific healthcare services in e-health, the scheme of priority for e-health services and the support of QoS in wireless networks and techniques or methods for IEEE 802.11 to guarantee the provision of QoS has also been assessed.
In e-health, medical services in remote locations such as rural healthcare centers, ambulances, ships as well as
home healthcare services can be supported through the applications of e-health services such as medical
databases, electronic health records and the routing of text, audio, video and images. Given this, an adaptive
resource allocation for a wireless network with multiple service types and multiple priorities have been
proposed. For the provision of an acceptable QoS level to users of e-health services, prioritization is an
important criterion in a multi-traffic network. The requirement for QoS provisioning in wireless broadband
medical networks have paved the pathway for bandwidth requirements and the real-time or live transmission
of medical applications. From the study, good performance of the proposed scheme has been validated by the
results obtained. The proposed wireless network is capable of handling medical applications for both normal
and life-threatening conditions as characterized by the level of emergencies. In addition, the bandwidth
allocation and admission control algorithm for IEEE 802.16- based design specifically for wireless
telemedicine/e-health services have also been presented in the study. It has been concluded that under busy
traffic conditions, the proposed architecture can used as a feasible and reliable infrastructure network for
telemedicine
Wireless Communications in the Era of Big Data
The rapidly growing wave of wireless data service is pushing against the
boundary of our communication network's processing power. The pervasive and
exponentially increasing data traffic present imminent challenges to all the
aspects of the wireless system design, such as spectrum efficiency, computing
capabilities and fronthaul/backhaul link capacity. In this article, we discuss
the challenges and opportunities in the design of scalable wireless systems to
embrace such a "bigdata" era. On one hand, we review the state-of-the-art
networking architectures and signal processing techniques adaptable for
managing the bigdata traffic in wireless networks. On the other hand, instead
of viewing mobile bigdata as a unwanted burden, we introduce methods to
capitalize from the vast data traffic, for building a bigdata-aware wireless
network with better wireless service quality and new mobile applications. We
highlight several promising future research directions for wireless
communications in the mobile bigdata era.Comment: This article is accepted and to appear in IEEE Communications
Magazin
Quality of service optimization of multimedia traffic in mobile networks
Mobile communication systems have continued to evolve beyond the currently deployed Third
Generation (3G) systems with the main goal of providing higher capacity. Systems beyond 3G
are expected to cater for a wide variety of services such as speech, data, image transmission,
video, as well as multimedia services consisting of a combination of these. With the air interface
being the bottleneck in mobile networks, recent enhancing technologies such as the High Speed
Downlink Packet Access (HSDPA), incorporate major changes to the radio access segment of
3G Universal Mobile Telecommunications System (UMTS). HSDPA introduces new features
such as fast link adaptation mechanisms, fast packet scheduling, and physical layer retransmissions
in the base stations, necessitating buffering of data at the air interface which presents a
bottleneck to end-to-end communication. Hence, in order to provide end-to-end Quality of
Service (QoS) guarantees to multimedia services in wireless networks such as HSDPA, efficient
buffer management schemes are required at the air interface.
The main objective of this thesis is to propose and evaluate solutions that will address the
QoS optimization of multimedia traffic at the radio link interface of HSDPA systems. In the
thesis, a novel queuing system known as the Time-Space Priority (TSP) scheme is proposed for
multimedia traffic QoS control. TSP provides customized preferential treatment to the constituent
flows in the multimedia traffic to suit their diverse QoS requirements. With TSP queuing, the
real-time component of the multimedia traffic, being delay sensitive and loss tolerant, is given
transmission priority; while the non-real-time component, being loss sensitive and delay tolerant,
enjoys space priority. Hence, based on the TSP queuing paradigm, new buffer managementalgorithms are designed for joint QoS control of the diverse components in a multimedia session
of the same HSDPA user. In the thesis, a TSP based buffer management algorithm known as the
Enhanced Time Space Priority (E-TSP) is proposed for HSDPA. E-TSP incorporates flow
control mechanisms to mitigate congestion in the air interface buffer of a user with multimedia
session comprising real-time and non-real-time flows. Thus, E-TSP is designed to provide
efficient network and radio resource utilization to improve end-to-end multimedia traffic
performance. In order to allow real-time optimization of the QoS control between the real-time
and non-real-time flows of the HSDPA multimedia session, another TSP based buffer management
algorithm known as the Dynamic Time Space Priority (D-TSP) is proposed. D-TSP
incorporates dynamic priority switching between the real-time and non-real-time flows. D-TSP
is designed to allow optimum QoS trade-off between the flows whilst still guaranteeing the
stringent real-time component’s QoS requirements. The thesis presents results of extensive
performance studies undertaken via analytical modelling and dynamic network-level HSDPA
simulations demonstrating the effectiveness of the proposed TSP queuing system and the TSP
based buffer management schemes
End-to-end QoS architecture for 4G scenarios
This paper describes the QoS architecture and the corresponding QoS signalling protocols to be developed inside the IST project Daidalos. We address the main results achieved in terms of the definition of the QoS components and its interfaces, the description of the application and network services, definition of the signalling scenarios for the integration of the QoS signalling with the application signalling and with mobility approaches, and specification of the intra- and inter- domain QoS control approaches. We also describe the QoS management of the system, through the Policy–based Management System, and a Real-time Network Monitoring system able to aid in admission control with the results of active and passive measurements. All the elements, interfaces and functionalities take into account multicast services and inherent broadcast networks
Mobility-based predictive call admission control and resource reservation for next-generation mobile communications networks.
Recently, the need for wireless and mobile communications has grown tremendously and it is expected that the number of users to be supported will increase with high rates in the next few years. Not only the number of users, but also the required bandwidth to support each user is supposed to increase especially with the deploying of the multimedia and the real time applications. This makes the researchers in the filed of mobile and wireless communications more interested in finding efficient solutions to solve the limitations of the available natural radio resources. One of the important things to be considered in the wireless mobile environment is that the user can move from one location to another when there is an ingoing call. Resource reservation ( RR ) schemes are used to reserve the bandwidth ( BW ) required for the handoff calls. This will enable the user to continue his/her call while he/she is moving. Also, call admission control ( CAC ) schemes are used as a provisioning strategy to limit the number of call connections into the network in order to reduce the network congestion and the call dropping. The problem of CAC and RR is one of the most challenging problems in the wireless mobile networks. Also, in the fourth generation ( 4G ) of mobile communication networks, many types of different mobile systems such as wireless local area networks ( WLAN s) and cellular networks will be integrated. The 4G mobile networks will support a broad range of multimedia services with high quality of service.New Call demission control and resource reservation techniques are needed to support the new 4G systems. Our research aims to solve the problems of Call Admission Control (CAC), and resource reservation (RR) in next-generation cellular networks and in the fourth generation (4G) wireless heterogeneous networks. In this dissertation, the problem of CAC and RR in wireless mobile networks is addressed in detail for two different architectures of mobile networks: (1) cellular networks, and (2) wireless heterogeneous networks (WHNs) which integrate cellular networks and wireless local area networks (WLANs). We have designed, implemented, and evaluated new mobility-based predictive call admission control and resource reservation techniques for the next-generation cellular networks and for the 4G wireless heterogeneous networks. These techniques are based on generating the mobility models of the mobile users using one-dimensional and multidimensional sequence mining techniques that have been designed for the wireless mobile environment. The main goal of our techniques is to reduce the call dropping probability and the call blocking probability, and to maximize the bandwidth utilization n the mobile networks. By analyzing the previous movements of the mobile users, we generate local and global mobility profiles for the mobile users, which are utilized effectively in prediction of the future path of the mobile user. Extensive simulation was used to analyze and study the performance of these techniques and to compare its performance with other techniques. Simulation results show that the proposed techniques have a significantly enhanced performance which is comparable to the benchmark techniques
Energy-Efficient Softwarized Networks: A Survey
With the dynamic demands and stringent requirements of various applications,
networks need to be high-performance, scalable, and adaptive to changes.
Researchers and industries view network softwarization as the best enabler for
the evolution of networking to tackle current and prospective challenges.
Network softwarization must provide programmability and flexibility to network
infrastructures and allow agile management, along with higher control for
operators. While satisfying the demands and requirements of network services,
energy cannot be overlooked, considering the effects on the sustainability of
the environment and business. This paper discusses energy efficiency in modern
and future networks with three network softwarization technologies: SDN, NFV,
and NS, introduced in an energy-oriented context. With that framework in mind,
we review the literature based on network scenarios, control/MANO layers, and
energy-efficiency strategies. Following that, we compare the references
regarding approach, evaluation method, criterion, and metric attributes to
demonstrate the state-of-the-art. Last, we analyze the classified literature,
summarize lessons learned, and present ten essential concerns to open
discussions about future research opportunities on energy-efficient softwarized
networks.Comment: Accepted draft for publication in TNSM with minor updates and editin
- …