基于3GPP2框架的无线移动网络的RSVP扩展研究

本文讨论了面向固定网络设计的RSVP协议应用于无线移动网络需要解决的问题,并针对3GPP2框架下的无线移动网络提出了一种RSVP扩展方案.该方案采用隧道预留技术建立端-端主动预留,为数据连接提供服务质量保证;采用移动预测和被动预留技术在移动节点可能进入的蜂窝内提前预留无线资源,提高切换成功的概率;通过采用主动切换技术减小预留路径调整的时间,进一步提高通信的连续性.     

网络移动无缝切换机理研究

网络移动通过移动路由器实现边缘移动网络节点间及其与骨干网络节点间的会话连续性。移动路由器在嵌套接入环境下的接入安全与切换延时已经成为网络移动发展的最大障碍。在分析网络移动无缝切换研究现状的基础上,提出基于协同模型的网络架构、基于移动模型的预切换方法等需要突破的关键技术以及相应的无缝切换技术思路,支持轻量可信切换、多穴负载均衡、嵌套路由优化,为设计具有服务质量和安全保证的端到端网络移动通信协议提供技术支撑。     

移动切换资源预留技术研究

论文介绍了移动通信中的QoS、资源预留协议及为保证各业务QoS的资源预留切换方案。在移动切换中对基于QoS保证的资源预留方案的研究现状进行了综述,并在资源预留方法方面提出了一种设想,最后指出了今后资源预留技术研究的趋势。     

移动互联网的资源管理

未来的移动通信系统将是一个全IP网络,核心网采用IP技术,边缘是不同制式的通信系统,因此移动互联网的资源管理显得至关重要。文中针对未来移动互联网的服务质量(QoS)保证问题,探讨移动互联网中的资源管理,详细讨论网络资源管理和无线资源管理中具体的QoS控制技术。对于网络资源管理,主要讨论端到端的资源预留问题,针对资源预留机制不完全适用于移动环境,提出几种改进方案;对于无线资源管理,主要讨论切换、呼叫接纳控制和功率控制技术。最后提出移动互联网资源管理有待进一步研究的课题。     

资源预留机制的研究

随着计算机网络的发展,如何保障网络的端到端QoS是一个重要的研究课题,研究资源预留机制的意图是要为IP网络提供支持各种性能需求的服务质量。本文主要研究了因特网中资源预留的过程和IP多媒体子系统在SIP会话建立过程中QoS资源预留机制的实现过程。     

资源预留机制的研究

随着计算机网络的发展，如何保障网络的端到端QoS是一个重要的研究课题。研究资源预留机制的意图是要为IP网络提供支持各种性能需求的服务质量。本文主要研究了因特网中资源预留的过程和IP多媒体子系统在SIP会话建立过程中QoS资源预留机制的实现过程。     

全IP移动通信网接入网的QoS保证机制研究

移动性管理和服务质量(Q0S)保证一直是移动通信网络中两个关键性问题.文章介绍了全IP移动通信网接入网部分的几种QoS实现机制,通过扩展QoS保证机制与微移动管理协议之间的耦合,提出了一种资源预留协议(RSVP)和Hawaii协议松耦合的方案,并以集成了RSVP和Hawaii的仿真平台对该方案进行了仿真.仿真结果表明,松耦合方案可以显著地提高切换过程中的QoS.     

基于802.11r的WLAN快速切换机制研究

根据IEEE 802.11r协议设计的WLAN快速切换机制,将密钥管理和QoS资源分配在重关联之前或重关联过程中实现,减小了切换带来的时延,并提供了可用的QoS资源,保证了会话的连续性,从而减少了切换导致的连接中断对实时业务的影响.     

基于GTP与PMIP协议的WLAN切换技术

运营商正面临着移动数据业务流量高速增长的压力,将WLAN网络融合到LTE与3G网络,可以提高网络协同性和利用率,从而解决运营商覆盖不足和带宽有限的窘境。运营商面对的关键挑战是在WLAN集成到移动核心网后,当它和其它接入网络发生切换时,如何保持会话连续性。本文就此问题提出了相关解决方案,并深入分析了技术原理与切换流程。     

移动卫星网络中基于最小费用的切换算法

对于移动卫星网络,合理的星地链路切换方案需要在保证最小切换时延的同时,能够最优地使用网络资源。该文通过引入业务的中断概率和费用模型,给出了切换过程中重路由的最优触发条件,提出一种基于最小费用的切换(SMCH)算法。该算法可在保证切换业务通信的连续性和时延等指标不被破坏的基础上,通过适当的触发重路由来降低切换费用。仿真表明该算法在保证切换业务的QoS,降低切换费用以及适应性、灵活性等方面都优于同类切换算法。     

Seamless proactive handover across heterogeneous access networks

Dual-mode handsets and multimode terminals are generating demand for solutions that enable convergence and seamless handover across heterogeneous access networks. The IEEE 802.21 working group is creating a framework that defines a Media Independent Handover Function (MIHF), facilitates handover across heterogeneous access networks, and helps mobile users experience better performance during mobility events. In this paper, we describe this 802.21 framework and also summarize a Media-independent Pre-Authentication (MPA) mechanism currently under discussion within the IRTF that can further optimize handover performance. We discuss how the 802.21 framework and the MPA technique can be integrated to improve handover performance. Finally, we describe a test-bed implementation and validate experimental performance results of the combined mobility technique.     

IEEE 802.21: Media independent handover: Features, applicability, and realization

Providing users of multi-interface devices the ability to roam between different access networks is becoming a key requirement for service providers. The availability of multiple mobile broadband access technologies, together with the increasing use of real-time multimedia applications, is creating strong demand for handover solutions that can seamlessly and securely transition user sessions across different access technologies. A key challenge to meeting this growing demand is to ensure handover performance, measured in terms of latency and loss. In addition, handover solutions must allow service providers, application providers, and other entities to implement handover policies based on a variety of operational and business requirements. Therefore, standards are required that can facilitate seamless handover between such heterogeneous access networks and that can work with multiple mobility management mechanisms. The IEEE 802.21 standard addresses this problem space by providing a media-independent framework and associated services to enable seamless handover between heterogeneous access technologies. In this article, we discuss how the IEEE 802.21 standard framework and services are addressing the challenges of seamless mobility for multi-interface devices. In addition, we describe and discuss design considerations for a proof-of-concept IEEE 802.21 implementation and share practical insights into how this standard can optimize handover performance.     

A novel media independent handover‐based approach for vertical handover over heterogeneous wireless networks

The key purpose for seamless mobility and service continuity between heterogeneous wireless networks is the handover. Vertical handover management is one of key challenges in such environment. To deal with some of these challenges, an IEEE 802.21 media independent handover (MIH) framework has been standardized. The main purpose of this standard is to offer a general interface for the handover by abstracting the link layer intelligence to higher layers. However, there still exist a number of limitations in MIH architecture. In this paper, a new architecture of improved MIH is presented to perform vertical handover between wireless heterogeneous networks. We focused on interworking architecture between wireless local area network and long term evolution advanced network with the use of MIH signaling to define an efficient vertical handover. A performance analysis model for the proposed MIH‐based vertical handover is derived. Analysis results show that the proposed method can be easily deployed in present multimedia service networks. Copyright © 2013 John Wiley & Sons, Ltd.     

Handover management in integrated WLAN and mobile WiMAX networks [recent advances and evolution of WLAN and WMAN standards]

Recently there has been much effort, in both academia and industry, to integrate a plethora of wireless technologies in order to provide ubiquitous broadband access to mobile users. Handover management is still one of the most challenging issues to be solved for seamless integration of wireless networks. This article addresses the integration of IEEE 802.11 WLANs and IEEE 802.16 WMANs, focusing mainly on the handover management aspects. First, we describe architectures, futuristic application scenarios such as the envisioned heterogeneous multihop wireless networks (HMWNs) and moving networks, as well as the related research issues. Second, we present IEEE 802.21, a new emerging standard aimed at providing a framework for media-independent handover (MIH) among heterogeneous networks. Finally, we discuss how the MIH framework can help handover management for the integrated network.     

Enabling Heterogeneous Mobility in Android Devices

The fast growing of mobile Internet users with the ability of using a wide diversity of access technologies such as Wi-Fi, WiMAX and UMTS/LTE, and the increasing proliferation of mobile devices with heterogeneous network interfaces, require versatile mobility mechanisms providing seamless roaming across those access technologies. Mobility agents such as Mobile IP and Fast MIPv6 are common, however, these solutions still have limitations when dealing with multiple link-layer technologies. In this context, the emerging standard IEEE 802.21 provides a framework which enables mobile agents and network operators to improve the handover process in heterogeneous networks. In this context, this paper presents and discusses the design and implementation of a mobility-aware solution for an Android device, using the IEEE 802.21 framework. A modified Android user terminal is proposed to improve the handover process, assuming a make-before-break approach. Resorting to an experimental testbed, the obtained results show that the proposed solution is an effective contribution to successfully accomplish seamless mobility of Android-based devices operating in 3G and Wi-Fi networks.     

An overview of IEEE 802.21: media-independent handover services

In recent years multitechnology-enabled terminals have become available. Such multimode terminals pose new challenges to mobility management. In order to address some of these challenges, the IEEE is currently working on a new specification on media-independent handover services (IEEE 802.21 MIH). The main aim of this specification is to improve user experience of mobile terminals by enabling handovers between heterogeneous technologies while optimizing session continuity. In this article we provide an overview of the current status of the IEEE 802.21 specification.     

Seamless service provision for multi heterogeneous access - seamless content delivery in the future mobile internet

The key enabling function for seamless mobility and service continuity among a variety of wireless access technologies is the handover. Handovers within the same radio system are addressed by the standardization bodies involved in the development of the corresponding technologies (e.g., 3GPP, 3GPP2, IEEE, DVB), while handovers between heterogeneous systems are managed by protocols developed by the IETF. However, the interoperability between radio access systems that is required to realize the vision of Beyond 3G calls for coordinated actions and integrated solutions combining individual strengths. This article reviews emerging protocols and architectures aiming to support intersystem handovers between nextgeneration wireless systems and presents an optimized handover framework built around the functionality introduced by the IEEE 802.21 standard. Mapping of this framework to the entities of the 3GPP evolved system architecture is discussed and handover procedures involving key entities of this architecture are presented.     

使用IEEE 802.21的WLAN与WiMAX网的融合与切换

为了给移动用户提供最好的无所不在的无线宽带接入,不同无线网的融合是当前通信领域的热点研究。而切换管理又是解决无线网无缝融合的最具挑战性的问题。文中讨论了IEEE 802.11WLAN与IEEE 802.16e移动WiMAX网的融合与切换管理。描述其结构和应用场景,介绍了IEEE802.21,它为介质独立的异类网切换提供了一个信令框架,提出了如何使用IEEE802.21解决WLAN与移动WiMAX网之间的切换,并给出了详细的切换过程。说明了使用IEEE 802.21解决WLAN与移动WiMAX网之间的切换是可行有效的。     

SIP-based IEEE802.21 media independent handover — a BT Intel collaboration

In this paper, we look at various mobility management protocols and handover frameworks in use in BT. We also report on the results from a collaborative proof of concept mixed network prototype for a seamless handover system using Intel’s early implementation of the IEEE802.21 media-independent handover standard. The paper reports the design, implementation and deployment issues/options of a handover mechanism using the Intel framework which includes a connection manager and mixed network IEEE802.21 adaptation layer together with BT’s SIP-based audio/video application in a heterogeneous Wi-Fi, WiMAX and Ethernet network environment.     

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.