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1.
Resource reservation protocol (RSVP) is a network‐control protocol used to guarantee Quality‐of‐Service (QoS) requirements for real‐time applications such as Voice‐over‐IP (VoIP) or Video‐over‐IP (VIP). However, RSVP was designed for end‐systems whose IP addresses do not change. Once mobility of an end‐system is allowed, the dynamically changing mobile IP address inevitably impacts on RSVP performance. Our study aims to first quantify the significance of this impact, and then propose a modified RSVP mechanism that provides improved performance during handoffs. Our simulations reveal that the deployment of standard RSVP over Mobile IPv6 (MIPv6) does not yield a satisfactory result, particularly in the case of VIP traffic. Fast Handovers for Mobile IPv6 (FMIPv6) was found to be providing the best performance in all tested scenarios, followed by Hierarchical Mobile IPv6 (HMIPv6) with a single exception: during low handoff rates with VoIP traffic, MIPv6 outperformed HMIPv6. We then designed a new RSVP mechanism, and tested it against standard RSVP. We found that the proposed approach provides a significant improvement of 54.1% in the Total Interruption in QoS (TIQoS) when deployed over a MIPv6 wireless network. For HMIPv6, performance depended primarily on the number of hierarchical levels in the network, with no improvement in TIQoS for single‐level hierarchy and up to 37% for a 5‐level hierarchy. FMIPv6 on the other hand, provided no room for improvement due to pre‐handoff signaling and the tunneling mechanism used to ensure a mobile node (MN)'s connectivity during a handoff, regardless of the RSVP mechanism used. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

2.
移动IPv6分层管理费用的分析与自适应优化   总被引:8,自引:0,他引:8       下载免费PDF全文
彭雪海  张宏科  张思东 《电子学报》2004,32(10):1690-1693
为综合优化分层域内外以网络传输花费和带宽占用为代表的通信管理费用,论文对实施分层移动IPv6前后的费用变化进行了理论分析,得出了判决是否适宜使用分层移动管理的准则,并在此基础上提出一种允许移动节点动态地根据切换频度和流量强度等参数选择适宜的移动管理机制的自适应优化方案.仿真结果表明该方案能获得比静止使用某种移动管理机制更好的资源使用效率,可望具有较好的实际应用价值.  相似文献   

3.
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   

4.
In recent years, with the development of mobile communication technologies and the increase of available wireless transmission bandwidth, deploying multimedia services in next generation mobile IPv6 networks has become an inevitable trend. RSVP (resource reservation protocol) proposed by the IETF is designed for hardwired and fixed networks and can not be used in mobile environments. This paper proposes a protocol, called Fast RSVP, to reserve resources for mobile IPv6. The protocol adopts a cross-layer design approach where two modules (RSVP module and Mobile IPv6 module) at different layers cooperate with each other. Fast RSVP divides a handover process with QoS guarantees into two stages: (1) setup of the resource reservation neighbor tunnel and (2) resource reservation on the optimized route. It can help a mobile node realize fast handover with QoS guarantees as well as avoid resource wasting by triangular routes, advanced reservations and duplicate reservations. In addition, fast RSVP reserves “guard channels” for handover sessions, thus greatly reducing the handover session forced termination rate while maintaining high performance of the network. Based on extensive performance analysis and simulations, Fast RSVP, compared with existing methods of resource reservation in mobile environments, performs better in terms of packet delay and throughput during handover, QoS recovery time after handover, resource reservation cost, handover session forced termination rate and overall session completion rate.  相似文献   

5.
蒋青  鲁艳 《通信技术》2008,41(2):129-131
移动IP是一个在Internet上基于网络层提供移动性支持功能的要求较高的VoIP业务,切换延迟将直接影响到话音质量,严重时甚至会中断正在进行的会话.文章借助ns2网络模拟器仿真分析了WLAN中基于MIPv6的移动VoIP切换性能.结果表明,MIPv6及其扩展协议的切换性能优劣顺序依次为:F-HMIPv6、FMIPv6、HMIPv6、MIPv6.尤其是F-HMIPv6协议,无论端到端延迟还是切换延迟,都得到了最大的改善.所得结论能为网络切换性能的进一步优化提供重要依据.  相似文献   

6.
The fast Internet evolution and rapid development of wireless technologies have made it possible for users to communicate while on the move. Mobile IPv6 (MIPv6) is a candidate solution for next generation mobile Internet. Despite its popularity, MIPv6 still suffers from various limitations, for example, lack of business model and management of enormous and discrete home agents, preventing it from being deployed in large‐scale commercial environments. Recently, the ID/Locator split architecture has demonstrated its significant predominance in next generation mobile networks. With the aim of pushing the global deployment of mobility support over IPv6, this study makes an effort to design and evaluate an operational mobility model over IPv6 (OMIPv6) based on the ID/Locator split architecture to tackle the problems raised by the current form of MIPv6. In particular, a distributed cloud mobility management system is employed to be responsible for maintaining the identification and locations of mobile hosts, and providing the name resolution services to the mobile hosts. Furthermore, this paper develops an analytical model considering all possible costs required for the operation of OMIPv6, and adopts it as a cost‐effective tool to evaluate various costs and operation overheads on the performance of the OMIPv6 protocol. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

7.
This paper describes a reservation protocol to provide real-time services to mobile users in an Integrated Services Packet Network. Mobility of hosts has significant impact on the quality of service provided to a real-time application. The currently proposed network system architecture and mechanisms to provide real-time services to fixed hosts are inadequate to accommodate the mobile hosts which can frequently change their point of attachments to the fixed network. Mobile hosts may experience wide variations of quality of service due to mobility. To reduce the impacts of mobility on QoS guarantees, a mobile host needs to make advance resource reservations at multiple locations it may possibly visit during the lifetime of the connection. The currently proposed reservation protocol in the Internet, RSVP, is not adequate to make such reservations for mobile hosts. In this paper, we describe a new reservation protocol, MRSVP, for supporting integrated services in a network with mobile hosts.  相似文献   

8.
We propose and analyze a cross-layer integrated mobility and service management scheme called DMAPwSR in Mobile IPv6 environments with the goal to minimize the overall mobility and service management cost for serving mobile users with diverse mobility and service characteristics. The basic idea of DMAPwSR is that each mobile node (MN) can utilize its cross-layer knowledge to choose smart routers to be its dynamic mobility anchor points (DMAPs) to balance the cost associated with mobility services versus packet delivery services. These smart routers are just access routers for MIPv6 systems except that they are capable of processing binding messages from the MN and storing the current location of the MN in the routing table for forwarding service packets destined to the MN. The MN’s DMAP changes dynamically as the MN roams across the MIPv6 network. Furthermore the DMAP service area also changes dynamically reflecting the MN’s mobility and service behaviors dynamically. Unlike previous mobility management protocols such as HMIPv6 that focus only on mobility management, DMAPwSR considers integrated mobility and service management. We develop an analytical model based on stochastic Petri nets to analyze DMAPwSR and compare its performance against MIPv6 and HMIPv6. We validate analytical solutions obtained through extensive simulation including sensitivity analysis of simulation results with respect to the network coverage model, the MN’s residence time distribution and the DMAP service area definition.  相似文献   

9.
Mobile IPv6 (MIPv6) is a work in progress IETF standard for enabling mobility in IPv6 networks and is expected to have wide deployment. We investigate an integrated mobility and service management scheme based on MIPv6 with the goal to minimize the overall network signaling cost in MIPv6 systems for serving mobility and service management related operations. Our design extends IETF work-in-progress Hierarchical Mobile IPv6 (HMIPv6) with the notion of dynamic mobility anchor points (DMAPs) for each mobile node (MN) instead of static ones for all MNs. These DMAPs are access routers chosen by individual MNs to act as a regional router to reduce the signaling overhead for intra-regional movements. The DMAP domain size, i.e., the number of subnets covered by a DMAP, is based on the MN’s mobility and service characteristics. Under our DMAP protocol, a MN interacts with its home agent and application servers as in the MIPv6 protocol, but optimally determines when and where to launch a DMAP to minimize the network cost in serving the user’s mobility and service management operations. We demonstrate that our DMAP protocol for integrated mobility and service management yields significantly improved performance over basic MIPv6 and HMIPv6.  相似文献   

10.
近年来,随着经济的发展和计算机的普及,Internet业务出现了爆炸性的增长,并且出现了许多新兴的业务,如IP电、话、视频点播、视频会议等,现有Internet只提供传统单一尽力传送(best—effort)业务,因而急需新的网络协议以支持未来分类业务所需的不同带宽和服务质量(QoS)保障,现有网络虽然可以通过ATM(Asynchronous Transfer Mode)来解决QoS问题。但由于ATM信元的开销在整个帧中占了30%,严重降低了网络的传输效率,故未来网络不可能使用它。新出现的RSVP(资源预留协议)根据其自身的特点,必然会替代ATM,成为下一代网络保证QoS的关键网络技术。下面详细介绍RSVP的特点以及它如何有效的与未来的IPv6相结合。  相似文献   

11.
There has been a rapid growth in the need to support mobile nodes in IPv6-based networks. IETF has completed to standardize Mobile IPv6 (MIPv6) and Hierarchical Mobile IPv6 (HMIPv6) for supporting IPv6 mobility. Even though existing literatures have asserted that HMIPv6 generally improves MIPv6 in terms of handover speed, they do not carefully consider the details of the whole handover procedures. In this paper, based on the current IETF standards of both MIPv6 and HMIPv6, we conduct a comprehensive study of all IP-level handover procedures: movement detection, duplicate address detection, and location registration. Based on this study, we provide a mathematical analysis on MIPv6 and HMIPv6 performance in terms of handover speed. From the analysis, we reveal that the average HMIPv6 handover latency is not always lower than the average MIPv6 handover latency. Furthermore, even the intra-domain handover latency of HMIPv6 is not reduced much compared with MIPv6 handover latency. A finding of our analysis is that optimization techniques for movement detection and duplicate address detection are essential to shortening HMIPv6 handover latency and increasing the benefit of HMIPv6.
Sung-Gi MinEmail:
  相似文献   

12.
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.  相似文献   

13.
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   

14.
基本的移动IPv6(MIPv6)切换延迟非常大,不能满足实时业务的要求。本文基于对MIPv6的切换时延的分析,提出了一种IEEE802.11无线局域网环境下MIPv6的低时延切换方法,该方法通过结合使用连接触发器和快速路由器公告,并通过IP地址与MAC地址的映射机制来优化切换过程。仿真结果表明,该方法能够有效降低节点切换过程的时延,同时其性能优于以往相关的工作。  相似文献   

15.
As IP has been extended from core networks to access networks, a mobile network can be considered as an overlay of a traditional cellular network and an IP network. SMS-MIPv6 attempts to integrate mobility management of these two kinds of networks. The basic idea behind SMS-MIPv6 is to exploit existing mobility management in the cellular network (i.e. in the form of well-defined short messages) to locate a Mobile Terminal (MT) in the IPv6 network. We should emphasize that the motivation of SMS-MIPv6 is not to replace or optimize existing mature mobility management schemes. On the contrary, as an entirely end-to-end mechanism for IPv6 mobility management, it provides an alternative mechanism for free peer-to-peer applications such as Voice over IP (VoIP) without support from mobile network operators. We describe the implementation of SMS-MIPv6 in detail and analyze its performance. The evaluation results show that SMS-MIPv6 achieves acceptable performance so that it can be deployed in most current mobile networks. It performs best in terms of signaling cost, data traffic overhead compared with Mobile IPv6 (MIPv6) and Proxy MIPv6 (PMIPv6). Moreover, SMS-MIPv6 can reduce the handover latency significantly, although it is considered as a mobility management scheme for global mobility. However, it increases the session initialization latency due to hybrid binding through the cellular network.  相似文献   

16.
Zohar Naor 《Ad hoc Networks》2013,11(7):2136-2145
A layer-3 mobility management scheme for an all-IP Wireless Access Network (WAN), and in particular for vehicular networks, is developed in this paper. The proposed method enables fast and reliable handoff. This feature is extremely important for high speed vehicular networks. Since vehicles are characterized by likely-predictable path, as well as very high speed, handoff events can and should be predicted in order to achieve fast and reliable handoff. As it is shown in this study, the proposed scheme can significantly reduce the packet loss ratio caused by frequent handoff events experienced by high speed vehicles. This scheme is topology-independent in the sense that it does not assume any network topology. The key idea is to use a topology-learning algorithm that enables to perform localized mobility management, by efficiently re-selecting a Mobility Anchor Point (MAP) node. The goal of the proposed scheme is to maintain a continues connection subject to user-dependent delay constraints, while minimizing the signaling cost and packet loss ratio associated with handoff events. This scheme is consistent with the existing mobility management schemes currently used in Mobile IP (MIP) and cellular networks, and it fits into the Hierarchical Mobile IPv6 (HMIPv6) scheme defined in Mobile IPv6 (MIPv6) for integrating mobile terminals with the Internet wired backbone.  相似文献   

17.
Recently, a network-based mobility management protocol called Proxy Mobile IPv6 (PMIPv6) is being actively standardized by the IETF NETLMM working group, and is starting to attract considerable attention among the telecommunication and Internet communities. Unlike the various existing protocols for IP mobility management such as Mobile IPv6 (MIPv6), which are host-based approaches, a network-based approach such as PMIPv6 has salient features and is expected to expedite the real deployment of IP mobility management. In this article, starting by showing the validity of a network-based approach, we present qualitative and quantitative analyses of the representative host-based and network-based mobility management approaches (i.e., MIPv6 and PMIPv6), which highlight the main desirable features and key strengths of PMIPv6. Furthermore, a comprehensive comparison among the various existing well-known mobility support protocols is investigated. Although the development of PMIPv6 is at an early stage yet, it is strongly expected that PMIPv6 will be a promising candidate solution for realizing the next-generation all-IP mobile networks.  相似文献   

18.
The support of voice over Internet Protocol (VoIP) services in next-generation wireless systems requires the coupling of mobility with quality of service. The mobile node can experience disruptions or even intermittent disconnections of an ongoing real-time session due to handovers. The duration of such interruptions is called disruption time or handover delay and can heavily affect user satisfaction. Therefore, this delay needs to be minimized to provide good-quality VoIP services. In this paper, the focus is on the network layer mobility, specifically on mobile Internet Protocols (MIPs), since they are natural candidates for providing mobility at layer 3. Using analytical models, the authors evaluate MIPv4, MIPv6, fast MIPv6 (FMIPv6), and hierarchical MIPv6 (HMIPv6) and compare their performances in terms of handover delay for VoIP services. To optimize the handover delay, the authors propose to use the adaptive retransmission timer described in this paper. The results obtained using the adaptive timer technique show that for a 3% frame error rate and a 128-kb/s channel, the handoff delay is about 0.075 s (predictive) and 0.051 s (reactive) for FMIPv6. It is around 0.047 s [intra-mobile anchor point (MAP)] and 1.47 s (inter-MAP) for HMIPv6, around 1 s for MIPv6, and 0.26 s for MIPv4  相似文献   

19.
Hierarchical Mobile IPv6 (HMIPv6) has been proposed by the Internet engineering task force (IETF) to compensate for such problems as handover latency and signalling overhead when employing Mobile IPv6 (MIPv6). HMIPv6 supports micro‐mobility within a domain and introduces a new entity, namely mobility anchor point (MAP) as a local home agent (HA). However, HMIPv6 has caused load concentration at a particular MAP and longer handover latency when an inter‐domain handover occurs. In order to solve such problems, this paper establishes a virtual domain (VD) of a higher layer MAP and proposes a MAP changing scheme. The MAP changing scheme enables complete handover by using binding‐update of the on‐link care of address (LCoA) only when inter‐domain handover occurs. In addition, the concentrated load of a particular MAP is distributed as well. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

20.
In wireless/mobile networks, users freely and frequently change their access points (APs) while they are communicating with other users. To support the mobility of mobile nodes (MNs), Mobile IPv6 (MIPv6) is used to inform the information of MN's home address and current care‐of‐address (CoA) to its home agent. MIPv6 suffers from a long delay latency and high packet losses (PLs) because MIPv6 does not support micromobility. A Hierarchical Mobile IPv6 (HMIPv6) is proposed which provides micromobility and macromobility to reduce handoff latency (HL) by employing a hierarchical network structure. In this paper, we propose a cross‐layer partner‐based fast handoff mechanism based on HMIPv6, called the PHMIPv6 protocol. Our PHMIPv6 protocol is a cross‐layer, layer‐2 + layer‐3, and cooperative approach. A cooperative node, called a partner node (PN), is adopted in the PHMIPv6 protocol. A new layer‐2 trigger scheme used in the PHMIPv6 protocol accurately predicts the next AP and then invites a cooperative PN in the area of the next AP. With the cooperation of the PN, the CoA can be pre‐acquired and duplicate address detection operation can be pre‐executed by the PN before the MN initializes the handoff request. The PHMIPv6 protocol significantly reduces the handoff delay time and PLs. In the mathematical analysis, we verified that our PHMIPv6 protocol offers a better HL than the MIPv6, HMIPv6, and SHMIPv6 protocols. Finally, the experimental results also illustrate that the PHMIPv6 protocol actually achieves performance improvements in the handoff delay time, PL rate, and handoff delay jitter. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

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