共查询到20条相似文献,搜索用时 10 毫秒
1.
Reactive Handover Optimization in IPv6-Based Mobile Networks 总被引:3,自引:0,他引:3
《Selected Areas in Communications, IEEE Journal on》2006,24(9):1758-1772
In recent years, there has been a rapid growth in the need to support moving hosts and moving networks in IPv6-based mobile networks. As the number of such hosts and networks grows, so will the demand for delay sensitive real-time applications, such as voice over IP (VoIP), that require seamless handover. Two well-known approaches to reduce the handover latency have been proposed in the literature: proactive and reactive approaches. While proactive handover is known to generally outperform reactive handover, its reliability and practicality are still questionable since it basically depends on predictive information which may be unreliable in some cases. In this paper, based on the standard specification for IPv6 mobility support, we analyze the existing movement detection and address configuration procedures which are the main components of reactive handover approach. We also propose a novel reactive handover procedure which employs our optimized movement detection and address configuration schemes. The proposal is simple and robust because it does not need any predictive information and it requires a minimum number of signaling messages. The performance evaluation shows that the proposal substantially reduces the signaling load on wireless/wired networks and its handover latency is reduced enough to support seamless services. 相似文献
2.
由于无线网络技术的多样性,用户在采用不同接入或存取技术的无线网络间的无缝切换是一个非常重要的课题,本文提出一种新的基于MIPv6的WLAN与GPRS网络融合方案和在这种结构下的无缝切换机制。 相似文献
3.
In this paper, we analyze the IPv6 handover over wireless LANs. Mobile IPv6 is designed to manage mobile nodes movements between wireless IPv6 networks. Nevertheless, a mobile node cannot receive IP packets on its new point of attachment until the handover completes. Therefore, a number of extensions to Mobile IPv6 have been proposed to reduce the handover latency and the number of lost packets. We focus on Fast Mobile IPv6 which is an extension of Mobile IPv6 that allows the use of L2 triggers to anticipate the handover. We compare the handover latency in four specific cases: basic Mobile IPv6, the forwarding method of Mobile IPv6, the Anticipated method, and the Tunnel-Based Handover. The results of the handover latency are calculated with the L2 properties of IEEE 802.11b. In particular, we take into account the L2 handover for different configurations of the wireless network. 相似文献
4.
Robert C. Chalmers Govind Krishnamurthi Kevin C. Almeroth 《Mobile Networks and Applications》2006,11(2):215-227
In the future Wireless Internet, mobile nodes will be able to choose between providers offering competing services at a much
finer granularity than we find today. Rather than months, service contracts may span hours or minutes. Connectivity, however,
is just one of many possible services. Providers will begin to offer network and application-level services targeted at improving
the overall wireless experience of the user. Determining the best path through the various networks will require accurate
information describing which services are being offered by each provider. In this paper, we model the process of propagating
this information as an instance of a distributed, hierarchical cache. Access routers actively discover and collect information
about the immediate network neighborhood on behalf of mobile nodes. Mobiles fill their own caches through queries to their
local access routers, and then employ the cached information to make informed, intelligent handover decisions. Through simulation,
we show that high cache hit rates at the mobile node can be achieved even when the discovery process at the access router
is incomplete. In comparison to static and centralized approaches, our dynamic approach requires less configuration and maintenance,
avoids single points of failure, and provides a scalable solution that spans administrative domains.
Robert C. Chalmers received his B.S. in Computer Science from the California State Polytechnic University, Pomona in 1997, and his M.S. in 2003
from the University of California in Santa Barbara. He is currently a Ph.D. candidate at the University of California in Santa
Barbara where his main research interests focus around leveraging intelligence within the network. Particularly, he has studied
multicast and its effect on resource utilization, as well as how to provide services for small, mobile devices in edge networks.
He was awarded the Ericsson Fellowship in 2001 and is currently a Eugene Cota-Robles Fellow.
Govind Krishnamurthi received an M.S. (Electrical Engineering) and Ph.D. degree (Computer Engineering) from the University of Washington and the
Iowa State University, in 1997 and 1999 respectively. He spent the summer of 1995 as an intern at Bellcore, Morristown, NJ.
He is a recipient of the Research Excellence Award from the Iowa State University for his Ph.D. thesis. Since the summer of
1999 he has been a Senior Research Engineer at the Nokia Research Center, Boston, MA. He has authored several publications
and holds 3 patents. His current interests deal with QoS, location based services and security issues in IP based wireless
networks.
Kevin C. Almeroth earned his Ph.D. in Computer Science from the Georgia Institute of Technology in 1997. He is currently an associate professor
at the University of California in Santa Barbara where his main research interests include computer networks and protocols,
multicast communication, large-scale multimedia systems, and performance evaluation. At UCSB, Dr. Almeroth is a founding member
of the Media Arts and Technology Program (MATP), Associate Director of the Center for Information Technology and Society (CITS),
and on the Executive Committee for the University of California Digital Media Innovation (DiMI) program. In the research community,
Dr. Almeroth is on the Editorial Board of IEEE Network, has co-chaired NGC 2000, Global Internet 2001, NOSSDAV 2002, and MMNS
2002; has served as tutorial chair for several conferences, and has been on the program committee of numerous conferences.
Dr. Almeroth is serving as the chair of the Internet2 Working Group on Multicast, and is a member of the IETF Multicast Directorate
(MADDOGS). He is also serving on the advisory boards of several startups including Occam Networks, NCast, Hidden Footprint,
and the Santa Barbara Technology Incubator. 相似文献
5.
This paper proposes a fast handover mechanism to provide a seamless multicast service for Mobile IPv6 hosts. With the proposed
Fast handover based on a Mobile IP-Multi casting (FMIP-M) protocol, the selection of a new multicast service method, service
preparation, and initialization procedures are all performed during the fast handover period, thereby enabling a reliable
and efficient multicast service. When mobile hosts move to other networks, they can encounter data loss, out-of-synch problems
for multicast data, and multicast service exchange latency. Therefore, the proposed FMIP-M allows the new access router to
select a suitable multicast service method according to the multicast service-related network conditions and supports a reliable
multicast transmission by compensating for data losses from the previous access router. An analysis is conducted of the overheads
associated with a fast multicast handover, including the signaling cost and multicast packet-forwarding cost, where the costs
are formulated based on timing diagrams, and compared with a fast handover using Mobile IPv6. The performance analysis and
numerical results confirm that the proposed FMIP-M provides a fast multicast handover and reliable service with a relatively
small signaling cost and packet-delivery cost. 相似文献
6.
Adaptive Route Optimization in Hierarchical Mobile IPv6 Networks 总被引:1,自引:0,他引:1
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. 相似文献
7.
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
8.
扩展移动IPv6以实现网络的移动 总被引:1,自引:0,他引:1
本文在深入研究和分析移动IPv6工作原理的基础上,指出了移动IPv6只支持单个节点移动这一局限性,针对这一局限性,提出了扩展移动IPv6协议以实现网络的移动,并对这种网络移动机制的原理和实现做了详细的论述。 相似文献
9.
IPv6 for Future Wireless Networks 总被引:5,自引:0,他引:5
The functionalities of the next generation Internet protocol, IPv6, havebecome increasingly interesting due to the current merging of the traditionalcellular mobile communications and the traditional data-communications intothe future wireless systems, as e.g., UMTS. IPv6 provides several enhancedfunctionalities requested for the future mobile systems. In this article thelargest advantages in relation to mobile systems are presented. Variousaspects of introducing IP throughout the entire mobile network (core, accessand termainals) are also presented along with an illustration of the abilitiesof the future wireless network. 相似文献
10.
Chong Shen Wencai Du Robert Atkinson Kae Hsiang Kwong 《Wireless Personal Communications》2012,62(2):329-361
We propose a dynamic mobility management framework for Internet Protocol version 6 (IPv6) and policy enforcement enabled heterogenous
wireless networks. Policies and policy rules are defined depending on network infrastructure facilities, service agreements
and negotiation results. Each traffic is coupled with an identifiable traffic flow while the heterogenous interface flow bindings
are regulated by polices. The network selection, flow distribution, handovers and mobility procedures are flexible and we
propose to improve the decision making via Multiple Attributes Decision Making (MADM). Techniques considered in the framework
include the IPv6 based Network Mobility (NEMO), multihoming capability, transparent vertical handovers, horizontal handovers
and dynamic policy enforcement matching process to improve the Quality of Service (QoS), Quality of Experience (QoE) and ubiquitous
connectivity. A experiment testbed and simulation models have been constructed to verify the mobility framework performance
in a heterogeneous WiFi, WiMax and UMTS hybrid environment. 相似文献
11.
WiMAX is a wireless metropolitan area network (WMAN) specified by IEEE 802.16. It provides the broadband wireless access for mobile devices. In such a system, to enable the mobility, the handover is supported to maintain the connectivity of the mobile station (MS) when it moves from the coverage of the serving base station (BS) to the coverage of a neighbor BS. In the handover process, scanning is required to find a suitable target BS, and network re-entry is needed to establish the new connection. However, in the standard handover process, a long latency to data transmissions is caused resulting in the serious interruption to ongoing services. In this paper, an improved handover scheme is proposed to reduce the latency introduced in the handover process by shortening the scanning and enhancing the network re-entry. The proposed scanning strategy reduces the latency by reducing the number of neighbor BSs to be scanned through estimating the rough location of the MS. The enhanced network re-entry reduces the delay by updating transport connection identifiers (CIDs) early to allow the fast resumption of active applications. Simulations were conducted to evaluate the performance of the proposed handover scheme. The results show that the proposed handover scheme reduces the data transmission latency during handover significantly. 相似文献
12.
快速层次移动IPv6切换性能分析及优化 总被引:1,自引:0,他引:1
移动IPv6技术中切换延时对实时应用影响很大。介绍了目前移动IPv6常用的快速移动和层次移动切换技术,描述其切换原理和过程。结合2种技术的优缺点,给出了一种新的快速层次移动IPv6的切换方案。利用NS-2对这3种切换方法进行仿真得到的结果表明,快速层次移动IPv6切换延时要小于快速移动IPv6和层次移动IPv6的切换延时,且降低了数据包丢失率,提高了网络的性能。 相似文献
13.
Luís M. L. Oliveira Joel J. P. C. Rodrigues André G. F. Elias Guangjie Han 《Wireless Personal Communications》2014,78(4):1849-1862
The wireless sensor networks (WSNs) concept was appeared in the middle of 90s and have been a subject under intensive research in the past few years. Several factors have contributed to this, but the potential for application of WSNs in almost every aspect of day-to-day life is the predominant one. This type of networks has been developed using proprietary solutions instead of standard solutions. More recently, the importance of standards motivated the use of IETF standards in WSNs, making the Internet integration easier. However, more efforts are necessary in order to provide a full integration. The WSNs use mainly IPv6 protocol, but the IPv4 is the predominant one in the Internet. As a consequence, IPv4 to IPv6 transition mechanisms must be provided to allow the interaction between all Internet connected devices independently of the supported IP version. It is also critical to provide a standard application interface to make easier the application development and independently of the hardware platform used. The RESTfull Web services can provide this standard interface. So, combine RESTfull Web services with IPv4 to IPv6 transition mechanisms can increase the WSN services dissemination. The transition mechanisms and the REST Web services are supported in the gateway in order to save the wireless sensor device resources’. The smartphone with Internet connectivity can also be the drive to the WSNs growth, because user-friendly applications can be used to retrieve and collect sensed data. This paper proposes a solution based on REST web services to permit the interaction between a mobile application and the IPv6 compliant WSN. 相似文献
14.
运营商网络IPv6演进的策略分析 总被引:1,自引:0,他引:1
本文首先分析了IPv6引入的必要性,以及IPv4和IPv6网络在相当长的时间内必然共存的事实,介绍了IPv4向IPv6演进和共存的各种机制,并就运营商网络的IPv6演进策略,做了简要的探讨. 相似文献
15.
基于IPv6的移动数据网络发展探讨 总被引:1,自引:0,他引:1
IPv6在设计时充分考虑了移动需求,并将移动IPv6作为IPv6的基本组成部分,因此IPv6在移动环境下可更好地支持端到端以及多媒体业务.随着IPv6标准的成熟,移动网络中逐渐引入IPv6也成为通信网络的重要发展方向.本文首先介绍移动数据通信和IPv6技术的发展现状,然后探讨了在移动网络中引入IPv6的策略,并给出了3G网络环境下IPv6地址分配方式以及移动IP技术的发展现状,分析了移动IPv6协议的优点,列举了需要进一步研究的问题,最后给出了结论和建议. 相似文献
16.
17.
Hayoung Oh Kibaek Yoo Jongkeun Na Chong-kwon Kim 《Wireless Personal Communications》2010,52(3):593-613
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
18.
The complementary characteristics of cellular networks and wireless local area networks (WLANs) make it attractive to integrate these two technologies. In this integrated heterogeneous environment, mobile stream control transmission protocol (MSCTP) is ideal to support vertical handover (VHO) between them by enabling a mobile client to freely switch between IP addresses acquired in different networks. In this paper, we show that the MSCTP-based VHO scheme suffers from poor throughput performance during WLAN to cellular forced VHOs. We propose a novel error recovery scheme called Sending-buffer Multicast-Aided Retransmission with Fast Retransmission (SMART-FRX) to improve performance during VHO by multicasting the buffered and new data over both WLAN and cellular links when handover losses occur. In addition, we propose a new analytical model for SCTP that takes into account the congestion window, the round trip time, the slow-start and congestion avoidance processes. By comparing numerical results from the proposed analytical model with simulation results, we demonstrate that our analytical model is able to predict the SCTP throughput accurately, with or without the SMART-FRX scheme. The analytical model provides a useful tool that can be extended to study the performance of SCTP in other applications. Analytical and simulation results show that the proposed SMART-FRX scheme can improve the SCTP throughput performance significantly in WLAN to cellular forced VHO situations. 相似文献
19.
In wireless sensor deployments, network layer multicast can be used to improve the bandwidth and energy efficiency for a variety of applications, such as service discovery or network management. However, despite efforts to adopt IPv6 in networks of constrained devices, multicast has been somewhat overlooked. The Multicast Forwarding Using Trickle (Trickle Multicast) internet draft is one of the most noteworthy efforts. The specification of the IPv6 routing protocol for low power and lossy networks (RPL) also attempts to address the area but leaves many questions unanswered. In this paper we highlight our concerns about both these approaches. Subsequently, we present our alternative mechanism, called stateless multicast RPL forwarding algorithm (SMRF), which addresses the aforementioned drawbacks. Having extended the TCP/IP engine of the Contiki embedded operating system to support both trickle multicast (TM) and SMRF, we present an in-depth comparison, backed by simulated evaluation as well as by experiments conducted on a multi-hop hardware testbed. Results demonstrate that SMRF achieves significant delay and energy efficiency improvements at the cost of a small increase in packet loss. The outcome of our hardware experiments show that simulation results were realistic. Lastly, we evaluate both algorithms in terms of code size and memory requirements, highlighting SMRF’s low implementation complexity. Both implementations have been made available to the community for adoption. 相似文献
20.
Vehicle to Infrastructure(V2I) communications aim to provide mobile users on the road low-cost Internet and driver safety services.However, to meet Quality of Service(QoS) requirements of various applications and efficiently utilize limited wireless channel resourc-es, the transport layer protocol has to perform effective rate control in low channel quality and frequent changing topology communica-tion environment. In this paper, we propose a novel rate-control scheme in infrastructure based vehicular networks that avoids conges-tion and starvation and promotes fairness in end-to-end V2I communications. In vehicular networks, a bottleneck roadside unit(RSU)keeps track of its buffer size, aggregate incoming rate, and link throughput, and appropriately allocates bandwidth to traversing flows.With feedback information from the RSU, source nodes dynamically adjust their sending rates to avoid buffer overflow or starvation atthe bottleneck RSU. Simulation results show that the proposed scheme can reduce not only packet losses owing to buffer overflow butalso buffer starvation time, which improves the utilization efficiency of wireless channel resource. 相似文献