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.     

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.     

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.     

Media-independent handover for seamless service provision in heterogeneous networks

The performance of current Internet applications is based mainly on the capabilities of the underlying network technologies. Modern access systems usually can satisfy delay, loss, or bandwidth requirements; however, design inconsistencies can lead to service degradation as the terminals move across different systems. In this article, the focal point is the satisfaction of service requirements during mobility and more specifically, how the emerging IEEE 802.21 standard enables seamless, inter-technology handover. Based on prior work and a well-known example of seamless mobility, the main seamless mobility principles are identified and used as the basis for further evaluating the potential of the IEEE 802.21 standard to meet the requirements of applications for minimum disruption during an inter-technology handover.     

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.     

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.     

Mobility using IEEE 802.21 in a heterogeneous IEEE 802.16/802.11-based, IMT-advanced (4g) network

Industry is defining a new generation of mobile wireless technologies, called in cellular terminology "fourth generation" or "4G." This article shows that a system combining extensions of two radio access technologies, IEEE 802.11 and IEEE 802.16, meets the ITU-R's "IMT-Advanced" or 4G requirements. The extensions are 802.16 m (100 Mb/s, 250 km/h) and 802.11VHT (1 Gb/s, low velocity). The focus of this article is to show how IEEE 802.21 (the emerging IEEE standard for media-independent handover services) supports ";seamless"; mobility between these two radio access technologies. This mobility integrates the two radio access technologies into one system. We conclude that an 802.11VHT + 802.16 m + 802.21 system is likely to be proposed to the ITU-R for IMT- Advanced 4G.     

A terminal‐controlled vertical handover decision scheme in IEEE 802.21‐enabled heterogeneous wireless networks

The seamless internetworking among heterogeneous networks is in great demand to provide ‘always‐on’ connectivity services with quality of service (QoS) provision, anywhere at anytime. The integration of wireless‐fidelity (Wi‐Fi) and wireless metropolitan area networks (WiMAX) networks can combine their best features to provide ubiquitous access, while mediating the weakness of both networks. While it is challenging to obtain optimized handover decision‐based dynamic QoS information, users can improve their perceived QoS by using the terminal‐controlled handover decision in a single device equipped with multiple radio interfaces. The IEEE 802.21 aims at providing a framework that defines media‐independent handover (MIH) mechanism that supports seamless handover across heterogeneous networks. In this paper, an multiple attributes decision making‐based terminal‐controlled vertical handover decision scheme using MIH services is proposed in the integrated Wi‐Fi and WiMAX networks to provide ‘always‐on’ connectivity QoS services. The simulation results show that the proposed scheme provides smaller handover times and lower dropping rate than the RSS‐based and cost function‐based vertical handover schemes. Copyright © 2009 John Wiley & Sons, Ltd.     

Intelligent Technique for Seamless Vertical Handover in Vehicular Networks

Seamless mobility is a challenging issue in the area of research of vehicular networks that are supportive of various applications dealing with the intelligent transportation system (ITS). The conventional mobility management plans for the Internet and the mobile ad hoc network (MANET) is unable to address the needs of the vehicular network and there is severe performance degradation because of the vehicular networks’ unique characters such as high mobility. Thus, vehicular networks require seamless mobility designs that especially developed for them. This research provides an intelligent algorithm in providing seamless mobility using the media independent handover, MIH (IEEE 802.21), over heterogeneous networks with different access technologies such as Worldwide Interoperability for Microwave Access (WiMAX), Wireless Fidelity (Wi-Fi), as well as the Universal Mobile Telecommunications System (UMTS) for improving the quality of service (QoS) of the mobile services in the vehicular networks. The proposed algorithm is a hybrid model which merges the biogeography-based optimization or BBO with the Markov chain. The findings of this research show that our method within the given scenario can meet the requirements of the application as well as the preferences of the users.     

Moving toward seamless mobility: state of the art and emerging aspects in standardization bodies

The challenge to provide seamless mobility in the near future emerges as a key topic in various standardization bodies. This includes first of all the support of seamless handover between homogeneous networks. Distinct technologies—such as IEEE 802.11WLANs (Wi-Fi) and IEEE 802.16 MANs WiMAX—have recently augmented such support to existing standards to enable seamless homogeneous handover. Cellular networks, in contrast, already included this inherently from the start. Currently considerable effort goes into coupling of different radio access technologies. Therefore, the second key topic in standardization is seamless heterogeneous handovers. IEEE, IETF, as well as 3GPP consider different approaches toward architectures and protocols enabling seamless mobility management. In this work, we discuss recent and on-going standardization activities within IEEE, IETF, and 3GPP toward seamless homogeneous as well as heterogeneous mobility support.     

基于媒体独立切换并提供QoS保证的跨UMTS和WiMAX无线异构网络的网络切换方案

The rapid growth and innovation of the various mobile communication technologies have caused a change in the paradigm of internet access. Wireless technologies such as WiMAX, WiFi and UMTS/LTE networks have shown great potential in dominating the wireless access markets. The existence of various access technologies requires a means for seamless internetworking to provide anywhere, anytime services without interruption in the ongoing session, especially in multimedia applications with rigid Quality of Services (QoS) requirements. The IEEE 802.21 Media Independent Handover (MIH) working group was formed to develop a set of mechanisms under a standard framework with the capability to support migration of mobile users across heterogeneous networks. Therefore, the implementation of handover is extremely important in the heterogeneous network environment. In order to guarantee various QoS requirements during handover execution especially in multimedia applications, in this paper we propose a novel MIH-based capacity estimation algorithm to execute handover with QoS provision supporting both horizontal and vertical handovers across UMTS and WiMAX networks. Simulation shows that the proposed mechanism achieves lower call dropping rate (highest approximate 3% ) and higher system throughput (average 92% ) than the basic handover method does.     

基于环境感知与MIH的无缝切换优化研究

网络多样化已经是当今接入网的一大特点,完成各种网络的准确切换和会话连续性保障是其中关键的两项。IEEE802.21框架能够保证移动终端(Mobile Node,MN)在多网络中自由移动,然而保证切换过程中QoS连续性仍是需要解决的问题。针对切换过程中的这两个要求,提出动态阈值和被动资源预留方法保证准时切换和会话连续性,通过仿真可以看到相对传统的固定阈值和无资源预留方法的情况,该方法对切换连续性有一定的改善。     

A Survey on Media Independent Handover (MIH) and IP Multimedia Subsystem (IMS) in Heterogeneous Wireless Networks

One challenge of wireless networks integration is to provide ubiquitous wireless access abilities and seamless handover for mobile communication devices between different types of technologies (3GPP and non-3GPP), such as Global System for Mobile Communication, Wireless Fidelity, Worldwide Interoperability for Microwave Access, Universal Mobile Telecommunications System and Long Term Evolution. This challenge is critical as mobile users are becoming increasingly demanding for services regardless of the technological complexities associated with them. To fulfil these requirements for seamless vertical handover (VHO) two main interworking frameworks have been proposed by IEEE Group and 3GPP for integration between the aforementioned technologies; namely, Media Independent Handover IEEE 802.21 and IP Multimedia Subsystem, where each of them requires mobility management protocol to complement its work, such as Mobile IP and Session Initiation Protocol, respectively. Various VHO approaches have been proposed in the literature based on these frameworks. In this paper, we survey the VHO approaches proposed in the literature and classify them into four categories based on these frameworks for which we present their objectives and performances issues.     

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.     

Design and analysis of an IEEE 802.21-based mobility management architecture: a context-aware approach

Broadband wireless technologies will soon become an integral part of daily life. In this paper we present the design rationale of a context-aware mobility management architecture for seamless handover in heterogeneous networks. Our proposal is a new cross-layer and interactive approach to seamless handover of users and their services. We present a simple though effective analytical model in typical deployment scenarios in heterogeneous networks with the use of the IEEE Media Independent Handover services. Such analytical model is used to evaluate the resulting handover delay when deploying common mobility protocols in our architecture, such as Mobile IP, Hierarchical MIP, and Proxy MIP.     

A Robust Seamless Handover Scheme for the Support of Multimedia Services in Heterogeneous Emerging Wireless Networks

With the rapid development of wireless technologies and numerous types of mobile devices, the need to support seamless multimedia services in Mobile and Ubiquitous Computing (MUC) is growing. To support the seamless handover, several mobility protocols such as Mobile IPv6 (MIPv6) (Johnson et al., Mobility Support in IPv6, IETF, RFC 3775, 2004) and fast handover for the MIPv6 (FMIPv6) (Koodli et al. Past handovers for mobile IPv6 (FMIPv6), IETF, RFC 4068, 2005) were developed. However, MIPv6 depreciates the Quality-of-Service (QoS) especially in multimedia service applications because of the long handover latency and packet loss problem. To solve these problems in the MIPv6, FMIPv6 is proposed in the Internet Engineering Task Force (IETF). However, FMIPv6 is not robust for the multimedia services in heterogeneous emerging wireless networks when the MN may move to another visited network in contrast with its anticipation. In MUC, the possibility of service failure is more increased because mobile users can frequently change the access networks according to their mobility in heterogeneous wireless access networks such as 3Generation (3G), Wireless Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (WiMax) and Bluetooth co-existed. In this paper, we propose a robust seamless handover scheme for the multimedia services in heterogeneous emerging wireless networks. The proposed scheme reduces the handover latency and handover initiation time when handover may fail through the management of tentative Care-of Addresses (CoAs) that does not require Duplicate Address Detection (DAD). Through performance evaluation, we show that our scheme provides more robust handover mechanism than other scheme such as FMIPv6 for the multimedia services in heterogeneous emerging wireless networks.     

基于MIH的WLAN/WiMAX宏移动性研究

下一代无线网络将是异构IP网络,为了提供无缝切换服务,结合IETF提议的移动IPv6(MIPv6)协议与IEEE802.21工作组提出介质独立切换(MIH)标准,设计出一种基于MIH异构网络宏移动性的垂直切换方案。在NS-2仿真环境中,验证了此方案的可用性,详细分析了网络切换时延和丢包率,并根据分析结果提出进一步研究方向。     

An enhanced radio resource management based MIH policies in heterogeneous wireless networks

The require of omnipresent wireless access and high data rate services are expected to increase extensively in the near future. In this context, heterogeneous networks, which are a mixture of different wireless technologies (LTE-advanced, LTE-advanced Pro, C-IoT (Cellular Internet of Thing), 5G WiFi, etc) are invited to enable important capabilities, such as high data rates, low latencies and efficient resource utilization in order to provide dedicated capacity to offices, homes, and urban hotspots. Mixing these technologies in the same system, with their complementary characteristics, to afford a complete coverage to users can cause various challenges such as seamless handover, resource management and call admission control. This article proposes a general radio resource management framework which can be supported by future network architectures. A combined call admission control, resource reservation algorithm and bandwidth adaptation based IEEE 802.21 MIH standard approach for heterogeneous wireless network is detailed in this framework. Our aims are to guarantee quality of service (QoS) requirements of all accepted calls, reduce new call blocking probability and handover call dropping probability, and maintain efficient resource utilization. Performance analysis shows that our proposed approach best guarantees QoS requirements.     

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.     

Network selection in heterogeneous access networks simultaneously satisfying user profile and QoS

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.