Mobility protocols and RSVP performance in wireless IPv6 networks: shortcomings and solutions

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 (TI_QoS) 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 TI_QoS 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.     

一种新的基于移动IPv6的快速切换方案

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。     

移动IPv6分层管理费用的分析与自适应优化

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.     

Multilayer Hierarchical Model for Mobility Management in IPv6: A Mathematical Exploration

The mobility solution provided by Mobile IPv6 (MIPv6) imposes too much signaling load to the network and enforces large handoff latency to end user. Hierarchical MIPv6 (HMIPv6) on the other hand, is designed by organizing MIPv6 in layered architecture and performs better than MIPv6 in terms of handoff latency and signaling load. Observation shows that, there is still possibility to shrink the handoff latency and the signaling load by further extending HMIPv6 into multiple layers. To explore this possibility of enhanced performance through layered architecture, this paper aimed at mathematical exploration of an N-layered MIPv6 network architecture in order to figure out the optimal levels of hierarchy for mobility management. A widespread analysis is carried out on various parameters such as location update frequency and cost, handoff latency and packet delivery cost. Influence of queuing delay on handoff latency is examined by modeling M/M/1/K queue in the architecture and user mobility is modeled using Markov chain. Analytical investigation reveals that three levels of hierarchy in MIPv6 architecture provide an optimal solution for mobility management.     

Hierarchical mobility management for fast handoff and load distribution in IPv6 networks

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.     

Performance Analysis of Hierarchical Mobile IPv6: Does it Improve Mobile IPv6 in Terms of Handover Speed?

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.

An adaptive hierarchical mobile IPv6 using mobility profile

The Hierarchical Mobile IPv6 (HMIPv6), which is based on the Mobile IPv6 (MIPv6), has been proposed by IETF to reduce registration control signaling. It separates micro‐mobility from macro‐mobility with the help of an intermediate mobility agent, called the mobility anchor point (MAP), and exploits a Mobile Node's (MN's) spatial locality. However, all packets from a Correspondent Node (CN) to an MN are delivered through the MAP. That causes delay in packets delivery and the congestion of packets in the MAP so that it results in deterioration of network capability. To alleviate these problems, we propose a Hierarchical Mobile IPv6 protocol using not only spatial locality but also temporal locality. We introduce a profile for management of these locality information. According to the information in the profile, some packets are directly delivered to an MN, if MN seems to reside for a long time in the current subnet. Also, we introduce a handover scheme with the help of an L2 trigger, so that the proposed scheme takes nearly the same handover delay time as HMIPv6. The other contribution of this paper is to suggest a mathematical modeling and analysis of network traffic costs, MAP processing costs and handover latency for both HMIPv6 and the proposed scheme. Copyright © 2004 John Wiley & Sons, Ltd.     

Fast and reliable handoff for vehicular networks

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.     

用于WLAN的低时延混合MIPv6切换机制

由于传统的WLAN切换时延较大。因此不适用于时延敏感业务。借鉴IETF提高切换速度的两种协议——FMIPv6、HMIPv6，提出一种提高切换速度的混合MIPv6机制。混合MIPv6机制采用分层管理，在二层进行切换之前提前配置地址，避免了三层切换需要的切换时延，减小了发送绑定更新消息的数量和距离，从而大大提高了WLAN的切换速度，为WLAN增值业务的发展提供了条件。     

DMAP: integrated mobility and service management in mobile IPv6 systems

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.     

Enhancing Security in Mobile IPv6

In the Mobile IPv6 (MIPv6) protocol, a mobile node (MN) is a mobile device with a permanent home address (HoA) on its home link. The MN will acquire a care‐of address (CoA) when it roams into a foreign link. It then sends a binding update (BU) message to the home agent (HA) and the correspondent node (CN) to inform them of its current CoA so that future data packets destined for its HoA will be forwarded to the CoA. The BU message, however, is vulnerable to different types of security attacks, such as the man‐in‐the‐middle attack, the session hijacking attack, and the denial‐of‐service attack. The current security protocols in MIPv6 are not able to effectively protect the BU message against these attacks. The private‐key‐based BU (PKBU) protocol is proposed in this research to overcome the shortcomings of some existing MIPv6 protocols. PKBU incorporates a method to assert the address ownership of the MN, thus allowing the CN to validate that the MN is not a malicious node. The results obtained show that it addresses the security requirements while being able to check the address ownership of the MN. PKBU also incorporates a method to verify the reachability of the MN.     

A New Enhanced Fast Handover Algorithm in Hierarchical Mobile IPv6 Network

1　Introduction　MobileIPv6requirestheMobileNode (MN)toregisterwiththeHomeAgent (HA)andtheCorre spondentNode (CN)whenitchangesitspointofattachmentintheInternet[1～ 3] .Therefore ,thiscauseMobileIPv6toincurlongdelayintheregis tration process,andaddsignalingtraffictothebackbonenetworkespeciallywhentheHAandCNarefarawayfromtheMN .Inordertominimizethisdelay ,andthesignalingoverhead presentinMobileIPv6,literatures[4～7] proposeHierarchicalMobileIPv6(HMIPv6)architectureandafasthan dover…     

集成AAA的HMIPv6认证与注册方案

在下一代互联网中,需要使用AAA保证网络安全和网络资源合理使用,但是AAA与移动IPv6的结合,对切换性能及网络安全带来影响,而切换与安全是移动环境的关键问题。论文提出了新的解决方案,将HMIPv6与AAA结合,实现认证与注册过程的统一及本地认证,提高切换性能,并在注册与认证的过程中对消息进行加密,保证传输的安全。分析表明,本方案实现了AAA机制与移动管理机制安全高效的融合。     

乒乓切换在移动IPv6扩展协议中的性能分析

 综合评价了多种移动IPv6扩展协议在基于端到端的TCP协议L3层的切换性能,模拟仿真了乒乓切换在MIPv6、FMIPv6、HMIPv6和FHMIPv6中的时延、吞吐量和丢包现象,提出了一种优化的FHMIPv6方案.该方案通过定义新的Hop-by－Hop 选项报头TM、 PCoA表和双向隧道表,实现MN的快速、平滑切换,比FHMIPv6进一步减少了时延,提高了吞吐量,降低了丢包率.     

一种新的WLAN环境下移动IPv6的低时延切换方法

提出了一种IEEE 802.11无线局域网环境下移动IPv6的低时延切换方法NDPR.在不依靠链路层触发的条件下,NDPR使用非均匀检测模型来减小切换检测产生的时延,降低了切换检测过程的开销.通过IP地址与MAC地址的映射机制和转交地址的预注册机制,NDPR减小了移动IPv6的移动检测和转交地址配置过程的时延.仿真结果表明,该方法不但能够有效降低节点切换过程的时延,而且其性能优于以往相关的工作.     

Adaptive Route Optimization in Hierarchical Mobile IPv6 Networks

By introducing a mobility anchor point (MAP), Hierarchical Mobile IPv6 (HMIP6) reduces the signaling overhead and handoff latency associated with Mobile IPv6. However, if a mobile node (MN)'s session activity is high and its mobility is relatively low, HMIPv6 may degrade end-to-end data throughput due to the additional packet tunneling at the MAP. In this paper, we propose an adaptive route optimization (ARO) scheme to improve the throughput performance in HMIPv6 networks. Depending on the measured session-to-mobility ratio (SMR), ARO chooses one of the two different route optimization algorithms adaptively. Specifically, an MN informs a correspondent node (CN) of its on-link care-of address (LCoA) if the CN's SMR is greater than a predefined threshold. If the SMR is equal to or lower than the threshold, the CN is informed with the MN's regional CoA (RCoA). We analyze the performance of ARO in terms of balancing the signaling overhead reduction and the data throughput improvement. We also derive the optimal SMR threshold explicitly to achieve such a balance. Analytical and simulation results demonstrate that ARO is a viable scheme for deployment in HMIPv6 networks.     

基于无线局域网的移动IPv6链路层切换

随着实时业务(如VOIP)的快速发展,移动IPv6技术的切换过程时延已经不能满足现代通信的需求,因此改进切换时延,提高切换质量很有必要.本文介绍了当一个移动节点(MN)尝试进行基于无线局域网的MIPv6链路层的切换时,利用邻居图算法或邻居缓存机制来减少扫描延迟,从而减少总切换延迟.     

IPv6 multihoming support in the mobile internet

Fourth-generation mobile devices incorporate multiple interfaces with diverse access technologies. The current Mobile IPv6 protocol fails to support the enhanced fault tolerance capabilities that are enabled by the availability of multiple interfaces. In particular, established MIPv6 communications cannot be preserved through outages affecting the home address. In this article, we describe an architecture for IPv6 mobile host multihoming that enables transport layer survivability through multiple failure modes. The proposed approach relies on the cooperation between the MIPv6 and the SHIM6 protocols.     

Optimization of Mobile IPv6-Based Handovers to Support VoIP Services in Wireless Heterogeneous Networks

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     

移动IPv6技术发展及应用展望

简述了移动IPv6的技术背景,从协议原理、移动机制以及注册过程等方面对其实现进行了分析,对网络移动性和几种移动IPv6改进技术发展进行了阐述,最后结合技术和业务发展趋势,对移动IPv6的应用进行了展望。