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1.
Multimode capability empowers mobile devices to select the appropriate network to meet the requirements of user and applications. However, network selection is a challenging task owing to heterogeneous nature of network access links. At the same time, pervasiveness of mobile communication networks accompanied by the advances in wireless devices has raised the user expectations of persistent service and quality. Therefore, it is important for a mobile device to take situation‐based and timely decisions while selecting an access network to ensure both user's and operator's demand. The existing standard, called IEEE 802.21 (media‐independent handover), considers mobile device signal‐strength parameter for network selection from a list of networks. This research has proposed a ranking algorithm to rank heterogeneous networks based on a set of parameters including user profile and QoS. It selects most suitable network owing to multiple handover scenarios. The simulation results have shown that the proposed scheme has successfully satisfied apparently the contradictory requirements related to user profiles and QoS simultaneously.  相似文献   

2.
An IP-based QoS architecture for 4G operator scenarios   总被引:7,自引:0,他引:7  
This article describes a global QoS architecture for multimedia traffic in mobile heterogeneous environments. This architecture supports both multiple access networks and multiple service provider scenarios. The architecture is able to provide QoS per user and per service, implementing the notion of a user profile associated network management in the case of heterogeneous and mobile network access is presented based on cooperative association between QoS brokers and authentication, authorization, accounting, and charging systems. The overall exchange of messages is exemplified for the case of a field test with specific optimizations for voice traffic.  相似文献   

3.
Mobility is gaining a tremendous interest among Internet users and wireless access networks are increasingly being installed to enable mobile usage. Internet mobility requires solutions to move between access networks with maintained network connectivity. Seamless mobility in turn means that the experience of using a service is unaffected while being mobile. Communication in next generation networks will use multiple access technologies, creating a heterogeneous network environment. Further, roaming between network service providers may take place. To enable mobile nodes to move between access networks within as well as between network service providers with minimal disruption, nodes should be able to maintain multiple active network connections. With the usage of multihomed nodes, seamless mobility can be achieved in already installed infrastructures, not providing mobility support. Mobility in heterogeneous access networks also requires network selections that scale for services. In this article we propose an architecture where application service providers and network service providers define service levels to be used by a mobile node and its user. The user selects a service and the service level from an application service provider. When performing access network selection, information received as part of an application service level will be used to find a network that supports the service required. The performance of available access networks will be monitored and considered when making the decision. Our proposed architecture provides solutions to move flows between interfaces in real-time based on network performance, quality of service signalling to correspondent nodes, and cancellation of flows to give way for more important traffic.  相似文献   

4.
5.
This paper proposes a mobility management scheme to provide a mobile node with high-quality handovers among heterogeneous wireless access networks. The proposed scheme employs a signaling architecture to support fast and reliable delivery of control messages by separating a control plane from a data transport plane in the core network. The proposed scheme is based on the network-based mobility management framework which requires the minimum modifications on terminal devices. With interaction between Layers 2 and 3, the proposed scheme accelerates the handover control procedures. It also enables a mobile subscriber to select a target network for a vertical handover with consideration of not only wireless signal strength but also user preference and quality-of-service status. The proposed scheme addresses the well-known problems of the Mobile IP-based approaches, triangular routing and bottleneck at the home agent, since it establishes a data tunnel for a mobile node along the shortest path between two different access networks. The simulation and experimental results indicate that our scheme provisions more efficient performance than the existing approaches in terms of handover latency, data packet loss, data delivery latency and load balancing.  相似文献   

6.
In vehicular communications across composite radio environments, the one prominent feature is network heterogeneity, which means that diverse radio access networks co-exist with each other. And another particular feature is group mobility, because multiple mobile equipments in the vehicle are moving at the same time. Therefore, with movement of vehicle, many mobile terminals (MTs) in a train or bus may operate vertical handover actions almost at the same time, which is regarded as the group vertical handover (GVHO). However, the current literatures on vertical handover (VHO) mainly focus on when to trigger handover and how to select the best target network for single user, if these VHO schemes were applied in vehicular communication scenario, it may lead to system performance degradation or network congestion, because the MTs with these VHO decision-making methods selfishly select the best networks regardless of the influences from other concurrent VHO users. Therefore, in order to provide reliable QoS guarantee and keep service connectivity for group mobility in vehicular communications across heterogeneous networks, three models are proposed in this paper to deal with the decision-making problems of incomplete and inaccurate information in GVHO scenario. Two of them adopt MT controlled VHO, while another adopts network assisted VHO. The performances of these schemes are studied with regard to the average transmission delay and average packet losses rate.  相似文献   

7.
Future mobile networks will be increasingly heterogeneous. Already today, wireless LAN is used by many mobile network operators as an addition to traditional technologies like GSM and UMTS; WiMax and 3GPP Long Term Evolution (LTE) will be added. Having heterogeneous wireless networks, one challenging research question needs to be answered: Which user should be served by which access network and when to conduct a handover? For such decisions, information on the state of networks and terminals is required. In this publication, we simulate mobile networks in which a central entity called Network Resource Management (N-RM) gives handover recommendations to mobile terminals. Based on these recommendations and local knowledge on link qualities, the terminals choose the cell to switch to. The N-RM should have a global view on the networks to give best recommendations. We designed the Generic Metering Infrastructure (GMI), a publish/subscribe system to collect information about access networks and terminals efficiently. We investigate the tradeoff between the signalling overhead caused by data collection and the quality of the handover decisions and show, how smart monitoring can reduce the amount of measurement data while ensuring the efficient use of heterogeneous networks. In addition, our simulation results show that combined local and central handover decisions significantly increase the capacity of the networks as compared to only local decisions.  相似文献   

8.
4G wireless networks will integrate heterogeneous technologies such as Wireless LAN and third generation (3G) cellular networks and have the capability to offer various services at any time as per user requirements, anywhere with seamless interoperability at affordable cost. One important challenge in such a heterogeneous wireless environment is to enable network selection mechanisms in order to keep the mobile users always best connected anywhere and at any time. In this paper, a multi-criteria access network selection algorithm is proposed in Worldwide Interoperability for Microwave Access–Wireless Fidelity environment, in order to facilitate the provision of high quality services and at the same time to satisfy different types of user service level agreements. Analytical hierarchy process (AHP) and grey relational analysis (GRA) methods are applying for optimal access network selection. The proposed methodology combines the AHP to decide the relative weights of criteria set according to network’s performance, as well as the GRA to rank the network alternatives. The advantages of the GRA method are that the results are based on the original data, the calculations are simple and straightforward, and finally it is one of the best methods to make decision under heterogeneous wireless network environment.  相似文献   

9.
摘 要:5G无人机通信网络和各种不同无线接入技术的结合使无线异构网络呈现多样化的发展趋势。然而,用户繁多且不同的业务请求对网络要求也不同,造成网络接入选择问题。提出了一种基于5G无人机通信的多智能体异构网络选择方法,将用户分为多个智能体,从用户端和网络端两个方面出发,将用户侧的时延和传输速率需求与网络侧的负载均衡需求综合考虑作为即时回报的相关参数,通过基于Nash Q-Learning的算法进行学习,得到异构网络环境下的网络选择决策模型。仿真结果表明,所提异构网络选择方法针对不同业务类型用户的需求均能选择合适的网络,同时均衡网络的负载,充分利用异构无线网络的资源。  相似文献   

10.
The tremendous growth rates of the Internet as well as the area of mobile communications give rise to the chance that the mobile Internet is most promising by combining both the Internet and mobile communications. These prospects are the motivation for the European research project BRAIN (Broadband Radio Access for IP‐based Networks), which is developing an open architecture for a broadband wireless mobile access network offering an integrated communication platform across heterogeneous networks and, thus, goes beyond current third generation systems and towards the mobile Internet. The project covers three major technical areas: support of seamless service provision in a mobile environment; the design of an IP‐based access network that will support non‐cellular technologies such as wireless LANs; and requirements of a broadband air interface suitable for hot spots. BRAIN is going to integrate HIPERLAN/2 with UMTS by means of an IP access network. The work is guided by a user‐centric top‐down approach ensuring that user functionality is the key driver of the project. This article will focus on that part of the BRAIN work which specifies the main interfaces of the BRAIN architecture and deals with aspects related to the support of Quality of Service and mobility. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

11.
异构无线网络的自适应垂直切换判决算法   总被引:1,自引:0,他引:1  
在未来的异构环境中,网络间的垂直切换将对QoS保证产生重要影响。针对移动终端在异构网络间切换不理想的问题,提出了一种自适应的垂直切换判决算法。采用基于用户多应用的代价函数对接入网络进行评估与选择,综合考虑移动终端当前的电池电量,判断当前业务是否需要进行网络切换,使移动终端能自适应地进行切换判决。仿真结果表明,该算法可以有效地延长移动终端的工作时间,减少乒乓效应,提高系统的切换性能,改善业务的QoS。  相似文献   

12.
One of the remarkable features of the next generation network is the integration of heterogeneous wireless networks,which enables mobile users with multi-mode terminals access to the best available network seamlessly.However,most of previous work only takes account of either maximizing single user’s utility or the whole network’s payoff,rarely considers the negotiation between them.In this paper,we propose a novel network selection approach using improved multiplicative multi-attribute auction(MMA).At first,an improved MMA method is put forward to define the user’s utility.Additionally,user cost is defined by considering allocated bandwidth,network load intensity and cost factor parameter.And last the best suitable network is selected according to the user’s performance-cost-ration.Simulation results confirm that the proposed scheme outperforms the existing scheme in terms of network selection’s fairness,user’s performance-cost-ration,load balancing and the number of accommodated users.  相似文献   

13.
王晶晶 《电子测试》2016,(21):107-108
近年来,移动通信技术蓬勃发展,多种网络并存,异构融合网络中的网络选择策略成为当前热点,本文引入了一种基于博弈论的网络选择方案,通过多级判决实现最佳接入.为了降低接入网络的多个用户间的干扰,本文在用户的发射端引入了基于SLNR的预编码,提高异构融合网络的整体性能.  相似文献   

14.
The mobile communications market has grown rapidly over the past ten years, but the market could reach saturation in the foreseeable future. More flexible mobile networks that can meet various user demands and create new market openings are required for further growth. Heterogeneous networks are more suitable than homogeneous networks for meeting a wide variety of user demands. There are two types of heterogeneous networks: a closed type, where network resources are deployed and operated by communication carriers, and an open type, where network resources can be deployed not only by existing operators, but also by companies, universities, and so on. It will be easy for newcomers to enter mobile businesses in an open heterogeneous mobile network so many innovative services are likely to be provided through cooperation between various companies or organizations. This article proposes a revised architecture for TISPAN-NGN, which corresponds to heterogeneous networks and open mobile markets, and presents a new business model.  相似文献   

15.
Support for host mobility an essential and necessary feature for roaming users who connect to wireless networks via access points. Access points may have different capabilities, be connected to different networks and be installed by different providers. A mobile host will discover multiple access points in this environment. In such an environment, a mobile host should be able to use the best available connection to communicate with a correspondent host and perhaps use multiple connections for different hosts. In areas with wireless local area network access, pockets with limited or no coverage could exist. Such restricted connectivity could be compensated by neighbor hosts who form an ad hoc network and relay packets until they reach an access point. This paper describes and discusses a proposed solution towards enabling and supporting connectivity in wireless networks. In the proposed solution the network layer software will evaluate and decide which wireless network connections to use. A Running Variance Metric (RVM) and a Relative Network Load(RNL) are used to measure the traffic load of access points in wireless access networks. RVM and RNL can be efficiently used for both infrastructure networks and ad hoc networks. Multihomed Mobile IP (M-MIP) is an extension of Mobile IP that enables mobile hosts to use multiple care-of addresses simultaneously. The extension enhances network connectivity by enabling the mobile host, the home agent and correspondent hosts to evaluate and select the best connection. A proposed gateway architecture using M-MIP that integrates wired IP networks with ad hoc networks is described. The M-MIP and gateway architecture using the RVM and RNL metrics have been validated with simulation studies and results are presented.  相似文献   

16.

Network selection is very important for a successful handover in a multi-tier heterogeneous networks. However, the primary challenges currently faced by research community is the lack of availability of network information at the mobile node side for efficiently select the most appropriate target network. It is practically difficult for an UE to get network information from base stations/access point of the neighbouring networks before connecting to them. In response to this, this paper proposes a network selection method that applies the knowledge of mobility data and the network load information to carry out an efficient handover for vehicle-to-infrastructure communication over multi-tier heterogeneous networks. We first derive key parameters, such as relative direction index, proximity index, residence time index, and network load index to select the best candidate network. A moving vehicle would be able to select the most appropriate target network by selecting one or more of the above parameters. We then test our algorithms by developing a dual mode vehicle On-Board Unit equipped with both Long Term Evolution-Advanced (LTE-A) and Wi-Fi network interface cards in OPNET simulator. The performance of the proposed handover method is evaluated by extensive OPNET-based simulation experiments. In the simulation model, we consider a multi-tier heterogeneous network comprising of a macro and multiple small cells of LTE-A and IEEE 802.11n technologies. Results show that our proposed handover method offers about 50% higher throughput and up to 43% higher packet delivery ratio than the conventional received signal strengths based network selection method.

  相似文献   

17.
谭晓衡  谢朝臣  郭坦 《电子学报》2018,46(3):582-588
针对无线通信异构网络切换中最优接入网的选择问题,现有研究主要集中于解决在两个网络间选择切换,而对于未来5G(5th Generation)通信系统中超密集网络的切换问题研究较少.本文就研究了5G无线通信系统中超密集异构网络的选择切换.文中提出了一种基于区域感知贝叶斯决策的联合垂直切换方式,该方案通过选择超密集异构接入网络的最优切换概率从而解决超密集网络切换问题.通过对移动用户(mobile station)从宏基站进入超密集服务小区,以及在小区内和小区间移动的不同场景进行仿真分析,研究结果表明本文决策方式能够准确地选择要切换的网络,因而该方案能够适用于超密集网络的应用场景.  相似文献   

18.
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.  相似文献   

19.
Nowadays many manufacturers are building mobile devices with multiple interfaces. Thus, users have access to different types of wireless access networks, which often, as for WLAN and cellular systems, coexists independently. The challenge is to make such multiple access networks to cooperate to have ubiquitous access and enhanced user quality of service. In this paper we present a scheme to allow inter-technology mobility by the introduction of an overlay network, which works on top of current (and future) networks. The proposed architecture controls all the aspect related to the mobility management: mobile node localization, handover decision and execution. The approach is distributed: it is the mobile node that decides which network to use, based on the offered service quality and the cost of the communication of the available networks, and triggers the handover execution directly to the corresponding host, using optimized SIP-based procedures. The overlay network copes with the mobile node localization. We implemented our solution in the laboratory to prove its validity and to test performance using real equipment. We also simulated the scheme using ns-3 to extend the evaluation to large scale deployments. In both test environments, our solution demonstrates high accurateness in selecting the network with the best quality as well as in supporting seamless vertical handover.  相似文献   

20.
The convergence of multitude radio access networks forming a cluster of seamless heterogeneous wireless environment has made the wireless communication industry meet the paradigm of always best connected, where various mobile devices are able to access numerous types of applications and services. However, achieving such landmarks could not be possible without difficulties which this paper tries to highlight some of the technical challenges underlying seamless vertical handover. It provides a general overview of the mobility management process including a brief on multi-homing mobility protocol and focuses on vertical handover decision making techniques, hi ghlighting some radio interface standar and analysed some handover approaches. The paper proposes fast intelligent inter-layer network selection as a new handover approach to select the best network among the candidate networks, where Quality of Service, handover delay and improved data bit rates are set to be achieved.  相似文献   

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