A mobility-based load control scheme in Hierarchical Mobile IPv6 networks

By introducing a mobility anchor point (MAP), Hierarchical Mobile IPv6 (HMIPv6) reduces the signaling overhead and handoff latency associated with Mobile IPv6. In this paper, we propose a mobility-based load control (MLC) scheme, which mitigates the burden of the MAP in fully distributed and adaptive manners. The MLC scheme combines two algorithms: a threshold-based admission control algorithm and a session-to-mobility ratio (SMR)-based replacement algorithm. The threshold-based admission control algorithm gives higher priority to ongoing mobile nodes (MNs) than new MNs, by blocking new MNs when the number of MNs being serviced by the MAP is greater than a predetermined threshold. On the other hand, the SMR-based replacement algorithm achieves efficient MAP load distribution by considering MNs’ traffic and mobility patterns. We analyze the MLC scheme using the continuous time Markov chain in terms of the new MN blocking probability, ongoing MN dropping probability, and binding update cost. Also, the MAP processing latency is evaluated based on the M/G/1 queueing model. Analytical and simulation results demonstrate that the MLC scheme outperforms other schemes and thus it is a viable solution for scalable HMIPv6 networks.     

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.     

Scheme for improving transmission performance of realtime traffic using priority queues in HMIPv6

Hierarchical Mobile IPv6 (HMIPv6) has been proposed by the Internet Engineering Task Force (IETF) to reduce handoff latency and signaling overhead. In the new protocol, Mobility Anchor Point (MAP) receives all packets in place of Mobile Node (MN) and MAP services are transferred to Care of Address (CoA) of MN. However, a MAP may be a single point of performance bottleneck because the MAP should not only handle signaling traffic but also process data tunneling traffic for all MNs registered in a MAP domain. So, MAPs need MAP management scheme for the multimedia services or real time services. We propose a MAP selection scheme that can select different MAPs according to the traffic characteristics of MNs and a multilevel queue processing method that can process binding updates based on the priorities of queues in a MAP when MNs send BU. Quantitative results of the performance analysis show that our proposal can reduce the location update cost by 31% and the total cost by 14%. With the multilevel queues, we could reduce the total cost by 12% and 17% for D=4 and D=8 respectively.     

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.     

DMAP-FR: Dynamic Mobility Anchor Points for Mobility,Service and Failure Recovery Management in Mobile IPv6 Systems

In this paper, we propose and analyze DMAP-FR, a mobility and service management scheme with failure recovery (FR) control in Mobile IPv6 systems. The basic idea behind DMAP-FR is to leverage access routers (ARs) running as regional mobility anchor points (MAPs) as in Hierarchical Mobile IPv6 (HMIPv6) for mobility and service management for mobile nodes (MNs). However, unlike HMIPv6, DMAP-FR allows the MAP of each MN to be determined dynamically based on the mobility and service characteristics of the MN and the failure behavior of ARs with the goal to minimize the network traffic. DMAP-FR incorporates fault tolerance mechanisms to allow the system to quickly recover from AR and MAP failures. We identify the best dynamic regional area size for the selection of MAP for each MN such that the overall network traffic due to servicing mobility, service and fault tolerance related operations is minimized. We demonstrate that DMAP-FR outperforms HMIPv6 for the same AR failure rate.     

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.     

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.     

Smart Routers for Cross-Layer Integrated Mobility and Service Management in Mobile IPv6 Systems

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.     

移动IPv6分层式路由管理模型的分析与研究

分层移动IPV6协议减少了注册延迟，但仍具有路由不够优化等问题。通过分析HMIPv6．提出一种基于分层机制的移动IPv6路由管理模型。该模型支持路由优化，能在域内、域间移动时实现快速切换以减少延迟．提高网络资源利用率。仿真分析结果验证模型的有效性．     

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…     

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.     

Dynamic multi-step paging scheme in PMIPv6-based wireless networks

In Proxy Mobile IP (PMIPv6) networks, proxy-registrations are performed even for idle MNs, resulting in unnecessary signaling traffic. Although there have been many IP paging techniques aimed at reducing the unnecessary location update, they focus only on Mobile IP (MIP) since they had been developed before PMIPv6 was proposed. Thus, adopting existing IP paging support is not sufficient to support mobility in PMIPv6 networks. For more efficient support, we propose a dynamic multi-step paging scheme that pages an MN in multiple incremental steps instead of flooding paging messages to a whole paging area to significantly reduce the signaling traffic caused by the proxy location updates in the PMIPv6 networks. In addition, to improve the paging delay performance that may be deteriorated by the multi-step paging, the proposed scheme configures paging area dynamically to raise the efficiency of locating MNs. The size of a paging area is designed to be determined based on the speed of an MN. We also develop a thorough analytical model for evaluating the performance of the proposed scheme compared with a static paging scheme in terms of the signaling cost and the paging delay. Thorough analysis and simulation demonstrate that in the PMIPv6 network, our paging scheme can significantly reduce the signaling cost for IP paging, achieving a shorter paging delay, compared to that of a paging scheme with a fixed paging area.     

基于DNS的代理移动IPv6位置管理机制

Proxy Mobile IPv6 (PMIPv6) is designed to provide a network-based localized mobility management protocol, but it does not handle the global mobility of hosts. In this paper, we propose a location management scheme based on Domain Name System (DNS) for PMIPv6 which can support global mobility by using DNS as a location manager. In addition, to support large numbers of mobile terminals and enhance network scalability a paging extension scheme is introduced to PMIPv6.To evaluate the proposed location management scheme, we establish an analytical model, formulate the location update cost and the paging cost,and analyze the influence of the different factors on the total signaling cost. The performance results show that our proposed scheme outperforms the basic PMIPv6 under various parameters in terms of reducing the signaling overhead and the proposed scheme reduces signaling overhead compared to the basic PMIPv6.     

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.     

A cross‐layer partner‐based fast handoff mechanism for IEEE 802.11 wireless networks

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.     

Integrating Mobile Ad Hoc Network to the Internet

A novel scheme is presented to integrate mobile ad hoc networks （MANETs） with the lnternet and support mobility across wireless local area networks （WLANs） and MANETs. The mobile nodes, connected as a MANET, employ the optimize d link state routing （OLSR） protocol for routing within the MANET. Mobility management across WLANs and MANETs is achieved through the hierarchical mobile IPv6 （HMIPv6） protocol. The performance is evaluated on a HMIPv6 based test-bed composed of WLANs and MANETs. The efficiency gain obtained from using HMIPv6 in such a hybrid network is investigated. The investigation result shows that the use of HMIPv6 can achieve up to 27% gain on reducing the handoff latency when a mobile roams within a domain. Concerning the reduction of the signaling load on the lnternet, the use of HMIPv6 can achieve at least a 54% gain and converges to 69%.     

Fast Handover in Hierarchical Mobile IPv6 Based on Motion Pattern Detection of Mobile Node

To meet the increasing communication requirement for people in ubiquitous environments, some handover schemes and improvements were proposed by the IETF in order to support mobility effectively. FHMIPv6 combines the advantages of FMIPv6 and HMIPv6. This paper proposes an improved scheme based on FHMIPv6 which mainly implements a combined-detection function between Mobile Node (MN) and Mobility Anchor Point (MAP) and calculates the Normalized Edit Distance to analyze the motion trail and estimate the motion pattern of MN. According to the estimating result, MAP determines the way MN attaches to the new access point so as to reuse some previous handover information and intellectualize the handover process to avoid redundant binding updating. Simulation results based on Network Simulation 2 (NS2) show that this improved scheme can reduce the packet’s loss rate and handover latency, enhance the throughput and improve the network performance as a whole, especially for MN with the Ping-Pong motion pattern.     

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.     

A novel distributed dynamic location management scheme for minimizing signaling costs in Mobile IP

Mobile IP is a simple and scalable global mobility solution. However, it may cause excessive signaling traffic and long signaling delay. Mobile IP regional registration is proposed to reduce the number of location updates to the home network and to reduce the signaling delay. This paper introduces a novel distributed and dynamic regional location management for Mobile IP where the signaling burden is evenly distributed and the regional network boundary is dynamically adjusted according to the up-to-date mobility and traffic load for each terminal. In our distributed system, each user has its own optimized system configuration which results in the minimal signaling traffic. In order to determine the signaling cost function, a new discrete analytical model is developed which captures the mobility and packet arrival pattern of a mobile terminal. This model does not impose any restrictions on the shape and the geographic location of subnets in the Internet. Given the average total location update and packet delivery cost, an iterative algorithm is then used to determine the optimal regional network size. Analytical results show that our distributed dynamic scheme outperforms the IETF Mobile IP regional registration scheme for various scenarios in terms of reducing the overall signaling cost.     

Resource-efficient network mobility support in Proxy Mobile IPv6 domain

The basic standard protocol for supporting network mobility (NEMO) (i.e., NEMO-BSP specified by IETF) introduces several performance problems, such as multiple tunneling overhead and packet delivery latency, because it exploits mobile IPv6 (MIPv6), which was proposed for host mobility. To improve the basic NEMO solution, two network-based NEMO approaches, rNEMO and N-PMIPv6, have been proposed. The rNEMO is able to reduce significant packet tunneling overhead. The N-PMIPv6, on the other hand, reduces location update cost, but it leads to packet tunneling overhead. Thus, they commonly waste network resources in both wired and especially wireless network. No efficient and practical solutions for minimizing both the location update overhead and packet tunneling overhead have been presented until now. This situation motivated us to propose a resource-efficient network mobility scheme (RENEMO), reducing resource utilization required for network mobility support. We show that the proposed RENEMO outperforms both rNEMO and N-PMIPv6 in terms of network resource.