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1.
The identifier/locator separation has been widely recognized as a feasible solution for addressing the current Internet's routing scaling problem. Moreover, such a separation solution in terms of mobility can keep connection survivability and support global seamless roaming. A critical challenge in supporting efficient mobility is how to update the identifier‐to‐locator mappings of mobile nodes (MNs). In this paper, we propose a mapping forwarding (MF) scheme for location management in the identifier/locator separation architecture. In the MF scheme, a tunnel router (xTR) is selected as an agent of an MN and keeps the MN's identifier‐to‐locator mapping invariable by setting up an MF chain. As long as the MN is managed by the same xTR, the MN's mapping stored in the xTR of each correspondent node of the MN does not need to be updated, thus reducing the location update signaling cost. Meanwhile, the unchanged mapping assures the correct forwarding of packets, which reduces mobility‐related disruption and enhances the location management's reliability. In addition, for the handoff in two MF chains, we propose a data‐triggered update scheme that can achieve route optimization. To evaluate the proposed MF scheme, we establish two analytical models and formulate the blocking probability and the total protocol cost. The performance results show how the blocking probability changes under various parameters and how the MF scheme can effectively reduce the blocking probability compared with the location management scheme without the MF strategy. Meanwhile, our analysis demonstrates that the MF scheme has a lower overhead when the mobility rate is high. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

2.
In the traditional Transmission Control Protocol/Internet Protocol (TCP/IP) stack, IP address represents not only the identifier but also the location of a node so that it can not provide global roaming seamless. To address this problem, MIP (Mobile IP) uses dynamical care-of-address to indicate the location of a mobile node (MN) and stable home address to indicate its identifier. However, such a separation of MIP can not support routing scalability, location privacy, and manageability. In this paper, we propose an identifier/locator split architecture which contains an overlay mapping system to store identifier-to-locator mappings and manage mobile nodes?? behavior. In addition, we design a novel mobility management scheme based on the identifier/locator split architecture (MMILS) which can address the above issues of MIP. To reduce the amount of signaling and enhance the performance, we distinguish micro-mobility and macro-mobility by introducing an Agent Tunnel Router (ATR). For micro-mobility, the ATR keeps the MN??s identifier-to-locator mapping invariable, so it avoids the mapping update in the mapping system and the Tunnel Route (TR) of each correspondent node. For macro-mobility, to support fast update and handover, we design a united mapping table in the ATR. And then, we estimate the number of entries and the required storage space to validate it feasible. To evaluate the efficiency of MMILS, we analyze the signaling cost by establishing an analytical model and implement it in our test-bed. The results demonstrate that the proposed scheme can effectively reduce signaling traffic and has a low handover delay compared to MIP and HMIP (Hierarchical Mobile IP).  相似文献   

3.
The location of mobile nodes must be managed to enable Internet connectivity of mobile ad hoc networks. Node mobility can be managed efficiently using a tree topology in which a mobile node registers with an Internet gateway along a tree path without using flooding. However, a node that loses connectivity to its parent has to find and connect to a new parent through a join-handshaking process. This tends to increase control overhead and impose some delay on on-going communication. Furthermore, the node may join its descendant because of the synchronization delay in updating topology change, creating a loop that significantly increases control overhead. We improve these problems by maintaining a quasi-tree topology in which a node maintains multiple parents. We also present a technique for detection and resolution of loops. The simulation results show that the quasi-tree mobility management approach far outperforms the traditional approaches and is highly robust against the significant increases in tree size and node mobility.  相似文献   

4.
提出了一种基于移动Mesh网络的定位系统,利用Mesh节点作为"锚"节点,建立相对坐标系,移动终端通过测量与"锚"节点之间距离,并通过TDOA定位算法获得自身相对位置信息。对移动Mesh网络定位系统可行性问题进行探讨,主要对移动Mesh网络条件下实现终端定位的性能进行了探讨,并对定位误差进行了必要的仿真验证。仿真结果表明该系统定位精度较高,可实现基于移动Mesh通信网络的终端定位功能。  相似文献   

5.
To overcome the inherent limitations of the current Internet architecture, such as lack of mobility support and security mechanism, research has begun on future Internet based on ID/locator split architecture. For the realization of future networks, it is necessary to consider the characteristics of their services and applications, as well as research on their basic architectures. The representative services include Cooperative Intelligent Transportation System (C-ITS) applications based on vehicle-to-vehicle/vehicle-to-infrastructure (V2V/V2I) communication which can prevent vehicular accidents, increase the efficiency of transportation systems, and reduce environmental pollution, all while improving passenger convenience. Since C-ITS services using V2I communication are tightly connected to both passenger and pedestrian safety, they require not only continuous network access but also secure communication regardless of the vehicle mobility. To provide continuous network access and secure communication to moving vehicles in future networks based on an ID/locator split approach, authentication and location updates of moving vehicles should be frequently performed, which results in significant signaling overhead. Therefore, to integrate V2I communication with an ID/locator split approach based on the (R1) HIMALIS architecture, in this paper we propose a novel mobility management scheme, called HIMALIS-VI, which can contribute to a delay reduction for the authentication and mitigating handover procedures at both the mobile hosts and network entities in an edge network.  相似文献   

6.
一种基于代理移动IPv6的全局移动性管理结构和协议   总被引:1,自引:0,他引:1  
该文定义一种基于代理移动IPv6的全局移动性管理结构和协议,简称为PMIPGMM。 在PMIPGMM中,由网络实体而不是移动节点完成移动性管理, 另外消除了移动节点和接入路由器之间分发数据的无线链路隧道负荷。为与熟知的层次移动IPv6协议比较,基于液体流移动性模型,分别给出了每个协议下,移动节点在平均域停留时间内产生的位置更新、数据分发和总费用函数。分别研究了各种系统参数对费用函数的影响。分析结果表明所提出的基于代理移动IPv6的全局移动性管理协议可以保证低的总费用。  相似文献   

7.
A predictive model‐based mobility tracking method, called dead reckoning, is developed for mobile ad hoc networks. It disseminates both location and movement models of mobile nodes in the network so that every node is able to predict or track the movement of every other node with a very low overhead. The basic technique is optimized to use ‘distance effect’, where distant nodes maintain less accurate tracking information to save overheads. The dead reckoning‐based location service mechanism is evaluated against three known location dissemination service protocols: simple, distance routing effect algorithm for mobility (DREAM) and geographic region summary service (GRSS). The evaluation is done with geographic routing as an application. It is observed that dead reckoning significantly outperforms the other protocols in terms of packet delivery fraction. It also maintains low‐control overhead. Its packet delivery performance is only marginally impacted by increasing speed or noise in the mobility model, that affects its predictive ability. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

8.
To enhance seamless source mobility support in the mobile NDN(Named Data Networking) environment,we propose a novel Locator Based Mobility support Approach,dubbed LBMA.In this approach,we assign a unique topologically layered locator to each AR(Access Route)in NDN network,and extend the AR with additional functionalities,such as caching and forwarding Interest packets on behalf of the source.Meanwhile,we add an optional field to the original NDN packet,and modify the Outgoing Interface(s) field in the AR's original FIB(Forwarding Information Base)entries,to record the mobility status and the current locator of the source.Specifically,the consumer in LBMA can continue the interrupted communication,without delivering Interest packets towards the old location of the source,nor waiting for all relevant devices completing the FIB entries updating.The performance analysis result indicates that LBMA has lower handoff cost and shorter handoff latency,compared with other existing source mobility support approaches.  相似文献   

9.
This paper specifies a global mobility management architecture and protocol procedure called GPMIP, which is based on Proxy Mobile IPv6. In GPMIP, mobility management is performed by the network entity rather than individual mobile nodes. The benefit is the elimination of the wireless link data delivery tunnel overhead between a mobile node and the access router. To compare with the well known Hierarchical Mobile IPv6 mobility management protocol, the location update, packet delivery, and total cost functions generated by a mobile node during its average domain residence time are formulated for each protocol based on fluid flow mobility model. Then, the impacts of various system parameters on the cost functions are analyzed. The analytical results indicate that the proposed global mobility management protocol can guarantee lower total costs. Furthermore, a qualitative comparison between GPMIP and some other global management protocols is also investigated.  相似文献   

10.
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.  相似文献   

11.
Wireless sensor networks (WSNs) are made up of many small and highly sensitive nodes that have the ability to react quickly. In WSNs, sink mobility brings new challenges to large-scale sensor networks. Almost all of the energy-aware routing protocols that have been proposed for WSNs aim at optimizing network performance while relaying data to a stationary gateway (sink). However, through such contemporary protocols, mobility of the sink can make established routes unstable and non-optimal. The use of mobile sinks introduces a trade-off between the need for frequent rerouting to ensure optimal network operation and the desire to minimize the overhead of topology management. In this paper, in order to reduce energy consumption and minimize the overhead of rerouting frequency, we propose an energy-aware data aggregation scheme (EADA) for grid-based wireless sensor networks with a mobile sink. In the proposed scheme, each sensor node with location information and limited energy is considered. Our approach utilizes location information and selects a special gateway in each area of a grid responsible for forwarding messages. We restrict the flooding region to decrease the overhead for route decision by utilizing local information. We conducted simulations to show that the proposed routing scheme outperforms the coordination-based data dissemination scheme (CODE) (Xuan, H. L., & Lee, S. Proceedings of the Sensor Networks and Information Processing Conference, pp. 13–18, 2004).  相似文献   

12.
Wireless mesh networks (WMNs) have emerged as one of the major technologies for 4G high-speed mobile networks. In a WMN, a mesh backhaul connects the WMN with the Internet, and mesh access points (MAPs) provide wireless network access service to mobile stations (MSs). The MAPs are stationary and connected through the wireless mesh links. Due to MS mobility in WMNs, mobility management (MM) is required to efficiently and correctly route the packets to MSs. We propose an MM mechanism named Wireless mesh Mobility Management (WMM). The WMM adopts the location cache approach, where mesh backhaul and MAPs (referred to as mesh nodes (MNs)) cache the MS's location information while routing the data for the MS. The MM is exercised when MNs route the packets. We implement the WMM and conduct an analytical model and simulation experiments to investigate the performance of WMM. We compare the signaling and routing cost between WMM and other existing MM protocols. Our study shows that WMM has light signaling overhead and low implementation cost.  相似文献   

13.
Quality of Service (QoS) support in Mobile Ad Hoc Networks (MANETs) for group communication necessitates design of reliable networks with multicast support mechanisms. Reliable network connectivity among MANET nodes require high quality links that have much less packet drops and reliable nodes considering node mobility and failures. Reliability of a network can be enhanced by designing an end-to-end network pipe that satisfies the required QoS in terms of in-flight packets from source to a destination as well as by using a path comprising of reliable nodes. In-flight packets may be computed by using bandwidth delay product (BDP) of a network pipe. To meet the QoS requirements of an application, BDP should be maintained stable irrespective of vibrant network conditions. In this paper, we propose a BDP based multicast routing scheme in MANET using reliable ring mesh backbone. The scheme operates in the following sequence. (1) Reliable node pairs are computed based on mobility, remaining battery power and differential signal strength. The node pairs also compute BDP between them. BDP of a reliability pair is assessed using available bandwidth and delay experienced by a packet between them. (2) Backbone ring mesh is constructed using reliable pair nodes and convex hull algorithm. Reliable ring mesh is constructed at an arbitrary distance from the centroid of the MANET area. (3) Multicast paths are found by discovering a path from source to each destination of the group with concatenated set of reliability pairs that satisfy the BDP requirement. (4) The ring mesh maintains high BDP on ring links and can recover in case of node mobility and failures. Results show that there is an improvement in terms of end-to-end delay, packet delivery ratio, control overhead, memory overhead and application rejection ratio as compared to the Enhanced On Demand Multicast Routing Protocol.  相似文献   

14.
We consider infrastructure-based mobile networks that are assisted by a single relay transmission where both the downstream destination and relay nodes are mobile. Selecting the optimal transmission path for a destination node requires up-to-date link quality estimates of all relevant links. If the relay selection is based on link quality measurements, the number of links to update grows quadratically with the number of nodes, and measurements need to be updated frequently when nodes are mobile. In this paper, we consider a location-based relay selection scheme where link qualities are estimated from node positions; in the scenario of a node-based location system such as GPS, the location-based approach reduces signaling overhead, which in this case only grows linearly with the number of nodes. This paper studies these two relay selection approaches and investigates how they are affected with varying information update interval, node mobility, location inaccuracy, and inaccurate propagation model parameters. Our results show that location-based relay selection performs better than SNR-based relay selection at typical levels of location error when medium-scale fading can be neglected or accurately predicted.  相似文献   

15.
面向高动态移动自组织网络的生物启发分簇算法   总被引:2,自引:0,他引:2       下载免费PDF全文
于云龙  茹乐  方堃  贾旭峰 《电子学报》2018,46(4):918-929
分簇可以有效地提高大规模移动自组织网络的性能.但高动态的移动自组织网络具有节点移动性强、网络拓扑变化快的特点,应用传统的分簇算法会造成网络性能迅速下降,频繁的簇拓扑更新造成了簇结构的不稳定和控制开销的增加.为了解决传统分簇算法无法适应高动态的大规模移动自组织网络的问题,提出了一种基于生物启发的移动感知分簇算法,该算法对多头绒泡菌的觅食模型进行了改进,使其适用于移动自组织网络领域.由于该算法与节点的移动特性进行了结合,所以该算法可以有效地在高动态移动自组织网络中进行簇的建立与维护.实验结果表明,相较于其他传统分簇算法,本文算法提高了平均链路连接保持时间和平均簇首保持时间,使得簇结构更加稳定,提高了对高动态、大规模移动自组织网络的适应能力.  相似文献   

16.
Multicasting has been extensively studied for mobile ad hoc networks (MANETs) because it is fundamental to many ad hoc network applications requiring close collaboration of multiple nodes in a group. A general approach is to construct an overlay structure such as multicast tree or mesh and to deliver a multicast packet to multiple receivers over the overlay structure. However, it either incurs a lot of overhead (multicast mesh) or performs poorly in terms of delivery ratio (multicast tree). This paper proposes an adaptive multicast scheme, called tree-based mesh with k-hop redundant paths (TBM k ), which constructs a multicast tree and adds some additional links/nodes to the multicast structure as needed to support redundancy. It is designed to make a prudent tradeoff between the overhead and the delivery efficiency by adaptively controlling the path redundancy depending on network traffic and mobility. In other words, when the network is unstable with high traffic and high mobility, a large k is chosen to provide more robust delivery of multicast packets. On the other hand, when the network traffic and the mobility are low, a small k is chosen to reduce the overhead. It is observed via simulation that TBM k improves the packet delivery ratio as much as 35% compared to the multicast tree approach. On the other hand, it reduces control overhead by 23–87% depending on the value of k compared to the multicast mesh approach. In general, TBM k with the small value of k offers more robust delivery mechanism but demands less overhead than multicast trees and multicast meshes, respectively.  相似文献   

17.
田永春  郭伟 《电子与信息学报》2004,26(10):1521-1526
该文介绍一种分层多跳无线网与其他骨干网络互连情况下的网络层移动性管理方案。它使用了包含逻辑家乡代理的宏移动性管理和将位置管理与路由和寻呼机制结合起来的微移动性管理的思想,以提高网络在战场等特殊情况下使用的可靠性和抗毁性,减小位置管理的开销,节省无线信道的带宽。  相似文献   

18.
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.
Mobile IP enables IP mobility support for mobile node (MN), but it suffers from triangular routing, packet redirecting, increase in IP header size, and the need for new infrastructure support. This paper details an alternative to enable terminal mobility support for MN. This scheme does not suffer from triangular routing effect and does not require dedicated infrastructure support such as home agent. It also does not increase the size of the IP header and does not require redirection of packets. These benefits are enabled with a tradeoff, which requires modifications on MN and its correspondent node. It uses an innovative IP-to-IP address mapping method to provide IP address transparency for applications and taps on the pervasiveness of SIP as a location service. From our analysis, we show that TMSP is much more efficient than mobile IP in terms of the number of hops as well as overhead. Our prototype implementation also shows that TMSP provides seamless communication for both TCP and UDP connections and the computational overhead for TMSP has minimal impact on packet transmission.  相似文献   

20.
For the effective mobility management of mobile nodes in Infrastructure-based Mobile Ad Hoc Networks, every mobile node is obliged to send a registration message to the Internet Gateway (IG) periodically. Not only do the registration messages and the additional control messages to establish paths from mobile nodes to the IG to send the registration messages incur a considerable amount of control overhead, but also they impose high traffic congestion on the mobile nodes in the vicinity of the IG which is referred to as the “funneling effect.” The control overhead and the funneling effect make it hard to handle mobility management with little impact on the performance of a routing protocol. Therefore, in this paper we propose a tree-based mobility management approach using a message aggregation technique that employs a novel timing model suitable for tree topology, referred to as a skewed wait time assignment technique, in order to maximize message aggregation. Despite its superior performance, this wait time assignment technique differs from the other techniques in that it does not require clock synchronization over nodes. By resorting to simulations, we show that the proposed approach can significantly alleviate the funneling effect as well as improve the performance of mobility management compared with the Tree-based and Quasi-tree based mobility management schemes.  相似文献   

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