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1.
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
2.
Internet Connectivity for Ad Hoc Mobile Networks 总被引:7,自引:0,他引:7
Sun Yuan Belding-Royer Elizabeth M. Perkins Charles E. 《International Journal of Wireless Information Networks》2002,9(2):75-88
The growing deployment rate of wireless LANs indicates that wireless networking is rapidly becoming a prevalent form of communication. As users become more accustomed to the use of mobile devices, they increasingly want the additional benefit of roaming. The Mobile IP protocol has been developed as a solution for allowing users to roam outside of their home networks while still retaining network connectivity. The problem with this solution, however, is that the deployment of foreign agents is expensive because their coverage areas are limited due to fading and interference. To reduce the number of foreign agents needed while still maintaining the same coverage, ad hoc network functionality can cooperate with Mobile IP such that multihop routes between mobile nodes and foreign agents can be utilized. In this work, we present a method for enabling the cooperation of Mobile IP and the Ad hoc On-Demand Distance Vector (AODV) routing protocol, such that mobile nodes that are not within direct transmission range of a foreign agent can still obtain Internet connectivity. In addition, we describe how duplicate address detection can be used in these networks to obtain a unique co-located care-of address when a foreign agent is not available. 相似文献
3.
A Mobile IP allows IP hosts to move between different networks without changing their IP addresses. Mobile IP systems supporting local registration were introduced to reduce the number of times a home registration with the remotely located home agent was needed. The local registration Mobile IP scheme enhanced performance by processing registration requests of mobile nodes at a local agent. The local registration approach may affect other aspects of the Mobile IP systems such as fault tolerance. In this paper, we briefly review previous solutions for supporting fault tolerance in local registration Mobile IP systems and propose a fault tolerance protocol with a backup foreign agent in a hierarchical local registration mobile IP to enhance the efficiency of such systems against foreign agent failures. We also describe the specification of the proposed protocol using LOTOS and perform its validation using MiniLite. Finally, we analyze the performance of our proposed fault tolerance protocol through simulation. 相似文献
4.
Global roaming in next-generation networks 总被引:5,自引:0,他引:5
Zahariadis T.B. Vaxevanakis K.G. Tsantilas C.P. Zervos N.A. Nikolaou N.A. 《Communications Magazine, IEEE》2002,40(2):145-151
Next-generation mobile/wireless networks are already under preliminary deployment. Mobile/wireless all-IP networks are expected to provide a substantially wider and enhanced range of services. However, an evolutionary rather than revolutionary approach to the deployment of a global all-IP wireless/mobile network is expected. To support global roaming, next-generation networks will require the integration and interoperation of mobility management processes under a worldwide wireless communications infrastructure. In this article global roaming is addressed as one of the main issues of next-generation mobile networks. Apart from the physical layer connectivity and radio spectrum allocation plans, mobility in a hierarchical structured scheme is discussed. An all-IP wireless/mobile network combined with inherited mobility schemes of each network layer and Mobile IP extensions is proposed. In this respect the mobility management mechanisms in WLAN, cellular, and satellite networks are analyzed, and an all-IP architecture is described and an enhanced roaming scenario presented 相似文献
5.
The rapid development of mobile businesses raises the need for exchanging information between mobile computing devices via
Internet. If a secure connection is necessary then a virtual private network (VPN) is essential. Currently, VPN protocols
set up secure connections between two nodes with fixed IP addresses. However, if several people work in a moving vehicle with
their mobiles or computers, the secure connection will be lost due to the IP change and a new connection has to be built from
scratch. The current solution to this problem is to run tunnels over Mobile IP (MIP). However, that is inefficient due to
double tunneling. In this paper, the authors add a novel form of mobility support to secure L2TP/IPsec tunnels which will
be shared by everyone in the vehicle using a Point-to-Point Protocol (PPP) wireless network. The mobility support properly
handles the IP change (users may even change to a different kind of network such as from Universal Mobile Telecommunications
System (UMTS) to Worldwide Interoperability for Microwave Access (WiMAX) without using an MIP, and without incurring tunnel-re-establishment
at handoff. The novel solution achieves better security than current mobility solutions for VPN, and supports fast handoff
in IPv4 networks. 相似文献
6.
Dynamic hierarchical mobility management strategy for mobile IP networks 总被引:14,自引:0,他引:14
Wenchao Ma Yuguang Fang 《Selected Areas in Communications, IEEE Journal on》2004,22(4):664-676
One of the major challenges for the wireless network design is the efficient mobility management, which can be addressed globally (macromobility) and locally (micromobility). Mobile Internet protocol (IP) is a commonly accepted standard to address global mobility of mobile hosts (MHs). It requires the MHs to register with the home agents (HAs) whenever their care-of addresses change. However, such registrations may cause excessive signaling traffic and long service delay. To solve this problem, the hierarchical mobile IP (HMIP) protocol was proposed to employ the hierarchy of foreign agents (FAs) and the gateway FAs (GFAs) to localize registration operations. However, the system performance is critically affected by the selection of GFAs and their reliability. In this paper, we introduce a novel dynamic hierarchical mobility management strategy for mobile IP networks, in which different hierarchies are dynamically set up for different users and the signaling burden is evenly distributed among the network. To justify the effectiveness of our proposed scheme, we develop an analytical model to evaluate the signaling cost. Our performance analysis shows that the proposed dynamic hierarchical mobility management strategy can significantly reduce the system signaling cost under various scenarios and the system robustness is greatly enhanced. Our analysis also shows that the new scheme can outperform the Internet Engineering Task Force mobile IP hierarchical registration scheme in terms of the overall signaling cost. The more important contribution is the novel analytical approach in evaluating the performance of mobile IP networks. 相似文献
7.
8.
In the mobile communication environments, Mobile IP is defined to provide users roaming everywhere and transmit information freely. It integrates communication and network systems into Internet. The Mobile IPv6 concepts are similar to Mobile IP, and some new functions of IPv6 bring new features and schemes for mobility support. Two major problems in mobile environments are packet loss and handoff. To solve those problems, a mobile management scheme – the cellular mobile IPv6 (CMIv6) is proposed. Our approach isbased on the Internet Protocol version 6 and is compatible with the Mobile IPv6 standard. Besides, it also combines with the cellular technologies which is an inevitable architecture for the future Personal Communication Service system (PCS). In this paper, {Cellular Mobile IPv6 (CMIv6)}, a new solutionmigrated from Mobile IPv6, is proposed for mobile nodes moving among small wireless cells at high speed. This is important for future mobile communication trends. CMIv6 can solve the problems of communication break off within smaller cellular coverage during high-speed movement when packet-switched data or the real-time voice messages are transmitted. Voice over IP (VoIP) packets were chosen to verify this system. The G.723.1 Codec scheme was selected because it has better jitter resistance than GSM and G729 in a packet-based cellular network. Simulation results using OPNET show smooth and non-breaking handoffs during high-speed movement. 相似文献
9.
Over the last decade, we have witnessed a growing interest in the design and deployment of various network architectures and
protocols aimed at supporting mobile users as they move across different types of networks. One of the goals of these emerging
network solutions is to provide uninterrupted, seamless connectivity to mobile users giving them the ability to access information
anywhere, anytime. Handoff management, an important component of mobility management, is crucial in enabling such seamless
mobility across heterogeneous network infrastructures. In this work, we investigate the handoff performance of three of the
most widely used mobility protocols namely, Mobile IP, Session Initiation Protocol (SIP), and Stream Control Transmission
Protocol (SCTP). Our empirical handoff tests were executed on an actual heterogeneous network testbed consisting of wired,
wireless local area, and cellular networks using performance metrics such as handoff delay and handoff signaling time. Our
empirical results reveal that Mobile IP yields the highest handoff delay among the three mobility protocols. In addition,
we also found that SIP and SCTP yield 33 and 55% lower handoff delays respectively compared to Mobile IP. 相似文献
10.
Mobile IP has been developed by IETF to handle mobility of Internet hosts at the network layer. Mobile IP suffers from a number
of drawbacks, including low survivability due to single-point failure of Home Agents. Recently,
Seamless
IP diversity based
Generalized
Mobility
Architecture (SIGMA) was proposed to support low latency, low packet loss mobility of IP hosts. In this paper, we show that
the location management scheme used in SIGMA enhances the survivability of the SIGMA-based mobile network. We develop an analytical
model to evaluate and compare the survivability of SIGMA with that of Mobile IP. Numerical results show the improvement in
system response time and service blocking probability of SIGMA over Mobile IP in the presence of hardware failures and Distributed
Denial of Service (DDoS) attacks.
The research reported in this paper was funded by NASA Grants NAG3-2922 and NNX06AE44G 相似文献
11.
Traditionally, wireless cellular communication systems have been engineered for voice. With the explosive growth of Internet applications and users, there is an increasing demand on providing Internet services to mobile users based on the voice-oriented cellular networks. However, Internet services add a set of radically different requirements on to the cellular wireless networks, because the nature of communication is very different from voice. It is a challenge to develop an adequate network architecture and necessary systems components to meet those requirements.This paper describes our experience on developing Internet services, in particular, mobile and multicast IP services, in PACS (Personal Access Communication Systems). Our major contributions are five-fold: (i) PACS system architecture that provides wireless Internet and Intranet access by augmenting the voice network with IP routers and backbone links to connect to the Internet; (ii) simplified design of RPCU (Radio Port Controller Unit) for easy service maintenance and migration to future IP standards such as IPv6; (iii) native PACS multicast to efficiently support dynamic IP multicast and MBone connectivity; (iv) optimization and incorporation of Mobile IP into PACS handoff mechanism to efficiently support roaming within a PACS network as well as global mobility between PACS networks and the Internet; (v) successful prototype design of the new architecture and services verified by extensive performance measurements of IP applications. Our design experience and measurement results demonstrate that it is highly feasible to seamlessly integrate the PACS networks into the Internet with global IP mobility and IP multicast services. 相似文献
12.
This article describes current and proposed protocols for mobility management for public land mobile networks (PLMNs), Mobile IP, wireless ATM, and satellite networks. The integration of these networks is discussed in the context of the next evolutionary step of wireless communications networks. First, a review is provided of location management algorithms for PCS implemented over a PLMN. The latest protocol changes for location registration and handoff are investigated for Mobile IP, followed by a discussion of proposed protocols for wireless ATM and satellite networks. Finally, an outline of open problems to be addressed by the next generation of wireless network service is discussed 相似文献
13.
Intelligent Handoff for Mobile Wireless Internet 总被引:6,自引:0,他引:6
Jon Chiung-Shien Wu Chieh-Wen Cheng Nen-Fu Huang Gin-Kou Ma 《Mobile Networks and Applications》2001,6(1):67-79
This paper presents an intelligent mobility management scheme for Mobile Wireless InterNet – MWIN. MWIN is a wireless service networks wherein its core network consisting of Internet routers and its access network can be built from any Internet-capable radio network. Two major standards are currently available for MWIN, i.e., the mobile IP and wireless LAN. Mobile IP solves address mobility problem with the Internet protocol while wireless LAN provides a wireless Internet access in the local area. However, both schemes solve problems independently at different layers, thereby some additional problems occur, e.g., delayed handoff, packet loss, and inefficient routing. This paper identifies these new problems and performs analyses and some real measurements on the handoff within MWIN. Then, a new handoff architecture that extends the features of both mobile IP and wireless LAN handoff mechanism was proposed. This new architecture consists of mobile IP extensions and a modified wireless LAN handoff algorithm. The effect of this enhancement provides a linkage between different layers for preventing packet loss and reducing handoff latency. Finally, some optimization issues regarding network planning and routing are addressed. 相似文献
14.
Mobile ATM offers a common wired network infrastructure to support mobility of wireless terminals, independent of the wireless access protocol. In addition, it allows seamless migration to future wireless broadband services, such as wireless ATM, by enabling mobility of end-to-end ATM connections. In spite of the diversity in mobile networking technologies (e.g., cellular telephony, mobile-IP, packet data services, PCS), all of them require two fundamental mechanisms: location management and handoff. This article describes different schemes for augmenting a wired ATM network to support location management of mobile terminals and handoff protocols for rerouting a connection data path when the endpoint moves. A prototype implementation of mobile ATM integrating mobility support with ATM signaling and connection setup, is presented. It shows how mobile ATM may be used to provide mobility support to an IP terminal using non-ATM wireless access 相似文献
15.
QU Zhao-wei~ L Ting-jie~. Research Center of Electronic Commerce Beijing University of Posts Telecommunications Beijing P.R. China . School of Economics Management Beijing University of Posts Telecommunications Beijing P.R. China 《中国邮电高校学报(英文版)》2005,12(4)
1IntroductionMobile users want to enjoy multi media and other real-ti me services in the Internet . Thus the Internet Engi-neering Task Force (IETF) has introduced the MobileIPv4[1]and Mobile IPv6[2]to interoperate seamlesslywith protocols that provide real-ti me services in the In-ternet. Multi-Protocol Label Switching ( MPLS) is afast label-based switching technology that integrates thelabel-swapping paradigm with network-layer routing[3].Resource Reservation Protocol ( RSVP)[4 ~… 相似文献
16.
《IEEE network》1998,12(4):4-10
We have developed a system and network architecture to provide IP services in the Personal Access Communications System (PACS). IP datagrams are delivered to PACS users through the PACS packet-mode data service, achieving more efficient usage of wireless resources and supporting multimedia applications such as MBone audio and video. The architecture presented in this article augments the PACS voice network with IP routers and backbone links, called the PACS Packet Network (PPN), and is connected to the global Internet via gateways. Compared to the cellular digital packet data (CDPD) network, which employs its own network-layer mobility protocol and thus supports roaming within the CDPD network only, we have incorporated Mobile IP into the PACS handoff mechanism to further achieve global IP mobility. We have also developed native PACS multicast and a group management scheme to efficiently handle dynamic IP multicast and MBone connectivity. These features seamlessly integrate PACS into the global Internet and provide standard-conforming IP services with global mobility 相似文献
17.
A Cross-Layer (Layer 2 + 3) Handoff Management Protocol for Next-Generation Wireless Systems 总被引:7,自引:0,他引:7
Next-generation wireless systems (NGWS) integrate different wireless networks, each of which is optimized for some specific services and coverage area to provide ubiquitous communications to the mobile users. It is an important and challenging issue to support seamless handoff management in this integrated architecture. The existing handoff management protocols are not sufficient to guarantee handoff support that is transparent to the applications in NGWS. In this work, a cross-layer (Layer 2 + 3) handoff management protocol, CHMP, is developed to support seamless intra and intersystem handoff management in NGWS. Cross-layer handoff management protocol uses mobile's speed and handoff signaling delay information to enhance the handoff performance of Mobile IP that is proposed to support mobility management in wireless IP networks. First, the handoff performance of Mobile IP is analyzed with respect to its sensitivity to the link layer (Layer 2) and network layer (Layer 3) parameters. Then, a cross-layer handoff management architecture is developed using the insights learnt from the analysis. Based on this architecture, the detailed design of CHMP is carried out. Finally, extensive simulation experiments are carried out to evaluate the performance of CHMP. The theoretical analysis and simulation results show that CHMP significantly enhances the performance of both intra and intersystem handoffs. 相似文献
18.
Integrated Mobility Management Methods for Mobile IP and SIP in IP based Wireless Data Networks 总被引:2,自引:0,他引:2
HyeJeong Lee Jee-young Song Sun-Ho Lee Sungwon Lee Dong-Ho Cho 《Wireless Personal Communications》2005,35(3):269-287
With developments in voice over IP (VoIP), IP-based wireless data networks and their application services have received increased
attention. While multimedia applications of mobile nodes are served by Session Initiation Protocol (SIP) as a signaling protocol,
the mobility of mobile nodes may be supported via Mobile IP protocol. For a mobile node that uses both Mobile IP and SIP,
there is a severe redundant registration overhead because the mobile node has to make location registration separately to
a home agent for Mobile IP and to a home registrar for SIP, respectively. Therefore, we propose two new schemes that integrate
mobility management functionality in Mobile IP and SIP. We show performance comparisons among the previous method, which makes
separate registration for Mobile IP and SIP without integration, and our two integrated methods. Numerical results show that
the proposed methods efficiently reduce the amount of signaling messages and delay time related to the idle handoff and the
active handoff. 相似文献
19.
Enabling Heterogeneous Mobility in Android Devices 总被引:1,自引:1,他引:0
Ricardo Silva Paulo Carvalho Pedro Sousa Pedro Neves 《Mobile Networks and Applications》2011,16(4):518-528
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. 相似文献
20.
Neng-Chung Wang Yung-Kuei Chiang Ji-Shuen Wong 《Wireless Personal Communications》2014,75(4):2181-2200
The research and development of next generation networks results in continuously growing in heterogeneity of wireless systems. Those systems also offer users the increasing possibility of roaming between different networks, which undoubtedly needs seamless integration. As mobile users continue to expand their requirements for seamless roaming, a good handoff mechanism is necessary especially for cellular networks and wireless local area networks. The most critical problem faced in the handoff mechanism is that users may need immediate data transmission. However, immediate data transmission is always obstructed because handoff latency occurs. In this paper, we propose a Hierarchical Mobile IPv6 handoff scheme using active measurement-foreign mobility agent to measure the residual bandwidth of each access point (AP) for handoff decision. As a result, the proposed scheme prevents whole efficiency from being affected by the registration time and improves immediate data transmission. In addition, a dual-threshold of the received signal strength is used to avoid the ping-pong effect. Simulation results show that the proposed scheme outperforms the traditional Mobile IPv6 and enhanced multilayer Hierarchical Mobile IPv6. 相似文献