QoS provisioning for multimedia wireless networks

As we move towards IP-based multimedia wireless networks with voice, video and data convergence, quality of service (QoS) provisioning will become an increasingly challenging task. One implication is that greater emphasis on managing the call admission and overall network resources will be needed. This paper presents a conservative and adaptive quality of service (CAQoS) framework for provisioning the QoS for both real-time and non-real-time traffic in a multimedia wireless network. Unlike most conventional schemes, which gradually scale down the bandwidth of ongoing connections to accommodate new connection/hand-off requests, CAQoS introduces an early scaling-down of bandwidth for new connections based on a designated provisioning model. The performance of a CAQoS system is evaluated through simulations of a realistic wireless environment. Simulation results show that CAQoS meets our design goals and outperforms conventional schemes.     

Scalable video coding and transport over broadband wirelessnetworks

With the emergence of broadband wireless networks and increasing demand of multimedia information on the Internet, wireless multimedia services are foreseen to become widely deployed in the next decade. Real-time video transmission typically has requirements on quality of service (QoS). However, wireless channels are unreliable and the channel bandwidth varies with time, which may cause severe degradation in video quality. In addition, for video multicast, the heterogeneity of receivers makes it difficult to achieve efficiency and flexibility. To address these issues, three techniques, namely, scalable video coding, network-aware adaptation of end systems, and adaptive QoS support from networks, have been developed. This paper unifies the three techniques and presents an adaptive framework, which specifically addresses video transport over wireless networks. The adaptive framework consists of three basic components: (1) scalable video representations; (2) network-aware end systems; and (3) adaptive services. Under this framework, as wireless channel conditions change, mobile terminals and network elements can scale the video streams and transport the scaled video streams to receivers with a smooth change of perceptual quality. The key advantages of the adaptive framework are: (1) perceptual quality is changed gracefully during periods of QoS fluctuations and hand-offs; and (2) the resources are shared in a fair manner     

A New Access Control Solution for a Multi-Provider Wireless Environment

The fundamental goal in future 4G mobile multi-service networks is to provide an efficient mobile computing environment. We presume that future terminals will be equipped with multiple heterogeneous wireless interfaces. We want to enable each user to seamlessly move between different providers networks. Besides seamless roaming, a key consideration is also devoted to quality-of-service provision. In this article, we propose a model and an architectural framework for supporting quality of service in the context of interconnected multi-provider wireless systems. The proposed integrated COPS-based management and RADIUS-based access control architecture will allow providers to offer multimedia services while optimizing the use of the underlying network resources. We suggest new concepts and protocols to provide solutions to these challenges and describe the French national research project named MMQoS aiming on building such future networks.     

Efficient Handover with Load Balancing: A Quality Perspective Approach

The heterogeneous wireless networking environment determined by the latest developments in wireless access technologies promises a high level of communication resources for mobile computational devices. Although the communication resources provided, especially referring to bandwidth, enable multimedia streaming to mobile users, maintaining a high user perceived quality is still a challenging task. The main factors which affect quality in multimedia streaming over wireless networks are mainly the error-prone nature of the wireless channels and the user mobility. These factors determine a high level of dynamics of wireless communication resources, namely variations in throughput and packet loss as well as network availability and delays in delivering the data packets. Under these conditions maintaining a high level of quality, as perceived by the user, requires a quality oriented mobility management scheme. Consequently a proposed smooth adaptive soft-handover algorithm, a novel quality oriented handover management scheme which unlike other similar solutions, smoothly transfer the data traffic from one network to another using multiple simultaneous connections.     

Building open programmable multimedia networks

Recent advances in distributed systems and transportable software and increasing demand for better quality of service (QoS) control in multiservice networks are driving a reexamination of network software architectures. We established the Comet (Control, Management, and Telemedia) Group at Columbia University's Center for Telecommunications Research to provide comprehensive understanding of network software architecture for the 1990s and beyond. This research focuses on developing new network architectures that support service creation, QoS control, and the joint allocation of computing and communications resources. This provides an opportunity to reconcile the perspectives of the computing and communication communities. Future multiservice (multimedia) networks will carry traffic such as video, audio, and computer data with diverse QoS requirements. Such networks will thus require that we develop ways to manage many physical and logical entities, services, and users     

QoS-aware TDMA for end-to-end traffic scheduling in ad hoc networks

The proliferation of low-cost broadband air interfaces has paved the way to the introduction of high-definition multimedia services in mobile and wireless networks. The cost for network resources utilization, when provisioning such services, will play a prominent role in their commercial success, since the more spare resources that can be used, the more cheaply the services can be delivered to the end users. In the context of promoting the role of ad hoc networks as service platforms for high quality multimedia applications, this article first discusses and classifies a set of issues involved in quality of service (QoS) provisioning in ad hoc networks and then presents a congestion-free TDMA algorithm for end-to-end network resources assignment via an optimized mechanism that relies on capacity requests and grants. The article also illustrates a method for invoking this algorithm to achieve efficient end-to-end QoS provisioning and concludes by showing the superiority of the proposed algorithm, as compared to other recently proposed TDMA scheduling algorithms     

QoE in video streaming over wireless networks: perspectives and research challenges

The deployment of 3G/LTE networks and advancements in smart mobile devices had led to high demand for multimedia streaming over wireless network. The rapid increasing demand for multimedia content poses challenges for all parties in a multimedia streaming system, namely, content providers, wireless network service providers, and smart device makers. Content providers and mobile network service providers are both striving to improve their streaming services while utilizing advancing technologies. Smart device makers endeavor to improve processing power and displays for better viewing experience. Ultimately, the common goal shared by content providers, network service providers, and smart device manufactures is to improve the QoE for users. QoE is both an objective and a subjective metric measuring the streaming quality experience by end users. It may be measured by streaming bitrate, playback smoothness, video quality metrics like Peak to Signal Noise Ratio, and other user satisfaction factors. There have been efforts made to improve the streaming experiences in all these aspects. In this paper, we conducted a survey on existing literatures on QoE of video streaming to gain a deeper and more complete understanding of QoE quality metrics. The goal is to inspire new research directions in defining better QoE and improving QoE in existing and new streaming services such as adaptive streaming and 3D video streaming.     

A Context-Aware Network Equipment for Dynamic Adaptation of Multimedia Services in Wireless Networks

B3G (Beyond 3rd Generation) networks is the next step in the wireless world. It will enable the delivery of services to end-users, on different underlying wireless access networks and customised to users’ context. Furthermore, seamless mobility between networks and switch of devices will be handled in a transparent way. In this paper, a Context-Aware Network Equipment (CANE) is introduced, that is able to dynamically adapt multimedia services according to the users’ context. The term context includes the users’ device, the users’ preferences, the network conditions as well as the service provider adaptation policies. As a proof of concept, an implementation of a CANE is given for a 802.11 network use-case. An evaluation of the prototype as well as simulations of the proposed solution, both for an audio streaming service and a video streaming service, are presented. The results show that adapting multimedia services in case of network overload can enable to maintain an acceptable quality of service delivered to end-users and even to allow more users to enjoy the services, which will not be possible without the CANE.     

CDMA EVDO网络中的QoS保障机制研究

随着3G无线分组网络的飞速发展,基于移动终端的实时多媒体业务需求也日趋广泛.如何保障诸如流媒体直播和可视通话等QoS要求较高的业务,必将成为一个重要的课题.对CDMA EVDO网络中的QoS保障机制进行了初步探讨,阐述了CDMA EVDO网络的QoS实现架构,并以终端MS源发呼叫的QoS协商过程为例,描述了其信令流程.     

Dynamic inter-domain MDS approach with secure seamless handover based on IEEE 802.21 MIH

The accessibility of available wireless access technologies with increasing demand for real time multimedia application becomes an essential part for mobile communication. Mobile users resourcefully utilize the heterogeneous environment for best quality of service (Qos) anywhere and anytime. Efficient handover optimization and intelligent mobility management is a key requirement for designing next generation wireless networks. Therefore, a novel IEEE 802.21 media independent handover (MIH) standard is adopted to provide an associated service for intelligent handover procedures. In addition, dynamic mobility management decision server (MDS) and IEEE 802.21a security extension for MIH services are also integrated in the proposed architectures to support fast, seamless and secure handover optimization in inter-domain mobility. Simulation results prove that the presented work resourcefully minimizes the packet loss, unnecessary handover probability and vertical handover delay by avoiding time consuming scanning process for target network discovery. The system thus achieves Qos guarantee by balancing the network load and throughput improvement for different applications with Proxy MIPv6 mobility management protocol.     

Network resource management for enterprise wide multimedia services

The support of broadband multimedia applications over an enterprise network poses a broad range of networking challenges for efficient resource management, intelligent switching, and access control for distributed information. We propose two server-based scheduling algorithms, with low computational complexity, to guarantee multimedia information synchronization at the destination, with minimum presentation delays and buffer requirements. We outline a communication framework, highlighting the issues and challenges faced by today's enterprise networks to support multimedia services. We describe the proposed connection establishment and resource allocation schemes in resource-constrained enterprise networks. The objective is to manage the limited resources of the network for maximum utilization. Towards this end we present a dynamic capacity allocation scheme to support connections for multiple users. Specifically, we show that the channel capacity allocation problem can be formulated as a quadratic programming problem. This allocation scheme is implemented at each intermediate switch to dynamically determine the capacity allocation. The effects of interswitch rate mismatch and network delay offset scheduling have also been incorporated in the management framework. In addition, we introduce the concept of route selection based on the requested network quality of service     

A new signaling protocol for intersystem roaming in next-generationwireless systems

In next-generation wireless systems, one of the major features that is different from the current personal communication service systems is the seamless global roaming. The mobile subscribers will be allowed to move freely across different networks while maintaining their quality of service for a variety of applications. To meet this demand, the signaling protocol of mobility management must be designed, supporting location registration and call delivery for roaming users who move beyond their home network. A new signaling protocol is proposed, emphasizing the active location registration for ongoing services during the mobile subscribers' movement. Another important goal of this new protocol is to reduce the overhead caused by mobility management so that the signaling traffic load and consumption of network resources can be reduced. The new protocol efficiently reduces the latency of call delivery and call loss rate due to crossing wireless systems with different standards or signaling protocols. The numerical results reveal that the proposed protocol is effective in improving the overall system performance     

Radio Network Aggregation for 5G Mobile Terminals in Heterogeneous Wireless and Mobile Networks

This paper provides a novel design concept for advanced mobile multi interface terminals with radio network aggregation capability and enhanced quality of service (QoS) provisioning for multimedia services (voice, video and data) in heterogeneous wireless and mobile networks. A new module is established which provides the best QoS and lowest cost for any given multimedia service by using simultaneously all available wireless and mobile access networks for a given traffic flow. This novel adaptive QoS module with adaptive QoS routing algorithm is called advanced QoS routing algorithm (AQoSRA), which is defined independently from any existing and future radio access technology. The performance of our proposal is evaluated using simulations and analysis with multi-interface mobile stations with AQoSRA within, carrying multimedia traffic in heterogeneous mobile and wireless environment with coexistence of multiple Radio Access Technologies, such as 3G, 4G as well as future 5G radio access networks. The analysis of the proposed framework for radio networks aggregation in advanced mobile terminals has shown overall better performances regarding the achievable throughput and multimedia access probability in heterogeneous wireless and mobile environment.     

Design of a Link Control Protocol for Multimedia Services in Wireless Local Communication

The convergence of wireless systems with multimedia services is the challengeof future generation wireless networks. The large variety of QoS requirementsof different media as well as the maintenance of synchronization of thedifferent streams to be presented at receiver, demand from the Data link layersome extra functionalities. In this paper, we present an enhanced approach forthe efficient management of multimedia applications in third-generationwireless networks. We advocate the use of multiple connections, one for eachtraffic component of the application, as the effective solution for thetransport of multimedia applications in future-generation wireless networks.The effectiveness of this scheme is guaranteed by providing a new link controltechnique that works on top of a PRMA-type access protocol which jointlymanages different streams of a multimedia application. For this purpose, wepropose a two-level priority mechanism (static and dynamic priorities)specified by higher protocol layers for link activation, channel access, andadmission control procedures specific to a multimedia application and foroptimizing the sharing of radio channel resources and management of thereservation queue at the base station. We expect this priority-based mechanismto perform well, especially during periods in which system traffic load ishigh, and to react well to the deterioration of multimedia service quality,in terms of both QoS parameters and the synchronization of its trafficcomponents.     

基于网络的视频通信系统的设计

随着移动通信和多媒体通信的飞速发展,构建于无线网络之上的多媒体服务已经被越来越多的用户所接受。2．5代移动通信CDMA的典型带宽为30～50kb／s,可以传输低速的视频,但是对多媒体应用来说,其质量还是未能达到要求。在现有技术条件下,如何在CDMA无线信道中保证视频流的质量以及如何扩大带宽提高视频质量,是值得研究的问题。文中提出了一种在多个CDMA通道中进行视频传输的框架,利用多个CDMA无线信道绑定的方法,提高了视频的帧率和分辨率。     

Wireless Access Method to Ensure Each User's QoS in Unpredictable and Various QoS Requirements

With the fast growth of Internet services, the demand for wireless high speed and advanced multimedia communications is rapidly increasing. Initial multimedia services have already been offered in the second generation systems (2-G). Currently, the third generation systems (3-G) are being deployed and it will support up to 2 Mbps packet oriented data services. But it is expected that the demand for higher data rate and large variety of high quality services will increase further more. Therefore, it is mandatory for the fourth generation systems (4-G) to take each user's quality of service (QoS) control into account.In this paper, we firstly describe an overview on requirements and technical issues for the 4-G systems, and wireless QoS control issues considering End-to-End QoS control in the IP network. Next, we propose broadband wireless access method for the fourth generation mobile communication systems. The proposed method for downlink is based on MC-CDMA (Multi-Carrier Code Division Multiple Access) with Multi-Timeslot, in which total downlink resources are split into three aggregates according to the QoS classes in time domain. It is considered that one of the typical advantages for the MC-CDMA is the effect of frequency diversity. We evaluated the effect by computer simulation using ray-traced propagation model. Simulation results show that short-term fading can be relaxed. Furthermore, we propose Multi-Level (ML) ARQ as one of the link adaptation methods. Simulation results show that the proposed scheme has a good performance with throughput and average retransmission power.     

Feasibility and modelling for convergence of optical-wireless network – A review

Now a days, the convergence of wireless and optical network gaining popularity to enhance the data carrying capacity, QoS and to support future multimedia applications. The queue theory plays an important role for analytically evaluating such converged networks. In the everyday state of affairs, queue phenomena are observed in the several situations like the health clinic, railway reservation system, automobile laundry centre, bank cash counter, call centre, etc. Similarly, the phenomenon of congestion is ascertained in the telephone network, computer network, communication systems and the Internet wherever nonstop enhancements need to be created to stay up with the quickly growing demand. The subsistence of these adverse clogging effects has lead toward the improvement of queuing theory-based statistical models. Therefore, these queues based statistical models answering to optimising queries corresponding to the way for assigning resources in converged optical and wireless networks. During this paper, a review on the role of the queuing model in wireless & optical communication is presented that concentrate on the present and future aspects of research.     

Multimedia Service Discrimination Based on Fair Resource Allocation Using Bargaining Solutions

We deal with a resource allocation problem for multimedia service discrimination in wireless networks. We assume that a service provider allocates network resources to users who can choose and access one of the discriminated services. To express the rational service selection of users, the utility function of users is devised to reflect both service quality and cost. Regarding the utility function of a service provider, total profit and efficiency of resource usage have been considered. The proposed service discrimination framework is composed of two game models. An outer model is a repeated Stackelberg game between a service provider and a user group, while an inner model is a service selection game among users, which is solved by adopting the Kalai‐Smorodinsky bargaining solution. Through simulation experiments, we compare the proposed framework with existing resource allocation methods according to user cost sensitivity. The proposed framework performed better than existing frameworks in terms of total profit and fairness.     

无线网络中的QoS和策略管理测试(续一)

上一期中,我们论述了策略管理和QoS在无线网络中的作用,并介绍了3GPP所定义的实现方式。在本期中,我们将继续讨论QoS和策略管理的测试方法,并介绍IXIA在一个北美运营商实验室里实现VoLTE测试的成功案例。6无线网络的服务质量验证全球运营商正花费数十亿美元购买设备和频谱来升级他们的移动宽带网络。通过网络升级,运营商旨在     

Dynamic QoS Allocation for Multimedia Ad Hoc Wireless Networks

In this paper, we propose an approach to support QoS for multimedia applications in ad hoc wireless network. An ad hoc network is a collection of mobile stations forming a temporary network without the aid of any centralized coordinator and is different from cellular networks which require fixed base stations interconnected by a wired backbone. It is useful for some special situations, such as battlefield communications and disaster recovery. The approach we provide uses CSMA/CA medium access protocol and additional reservation and control mechanisms to guarantee quality of service in ad hoc network system. The reason we choose CSMA protocol instead of other MAC protocols is that it is used in most of currently wireless LAN productions. Via QoS routing information and reservation scheme, network resources are dynamically allocated to individual multimedia application connections.