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1.
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   

2.
As the rapid development of wireless technologies and increasing communication need of people in ubiquitous environment, some handover schemes and improvements were proposed by the IETF in order to support mobility effectively. In addition, mobile Stream Control Transmission Protocol (mSCTP) proposed by the IETF is a new transport protocol supporting mobility and with a built-in feature called Multi-homing has attracted much attention from the research communities. Multi-homing is convenient to introduce IP diversity in mobility management. A seamless handover architecture called SIGMA based on mSCTP has better performance than Mobile IPv6 enhancements. However, the handover performance in SIGMA remains low if the mobile host moves at a fast speed. Aiming at this problem, we propose SHSBM, a Smooth Handover Scheme based-on mSCTP. SHSBM adopts the advantage of SIGMA, and utilize Buffer and Tunnel to better serve fast-moving users. Additionally, we propose two strategies to solve the problem caused by Buffer-scheme—sequence Out of Order. Criteria for performance evaluation including the packets’ loss rate, throughput and handover latency compared with SIGMA and Mobile IPv6 enhancements.  相似文献   

3.
Traditionally, wireless cellular communication systems have been engineered for voice. With the explosive growth of Internet applications and users, there is an increasing demand on providing Internet services to mobile users based on the voice-oriented cellular networks. However, Internet services add a set of radically different requirements on to the cellular wireless networks, because the nature of communication is very different from voice. It is a challenge to develop an adequate network architecture and necessary systems components to meet those requirements.This paper describes our experience on developing Internet services, in particular, mobile and multicast IP services, in PACS (Personal Access Communication Systems). Our major contributions are five-fold: (i) PACS system architecture that provides wireless Internet and Intranet access by augmenting the voice network with IP routers and backbone links to connect to the Internet; (ii) simplified design of RPCU (Radio Port Controller Unit) for easy service maintenance and migration to future IP standards such as IPv6; (iii) native PACS multicast to efficiently support dynamic IP multicast and MBone connectivity; (iv) optimization and incorporation of Mobile IP into PACS handoff mechanism to efficiently support roaming within a PACS network as well as global mobility between PACS networks and the Internet; (v) successful prototype design of the new architecture and services verified by extensive performance measurements of IP applications. Our design experience and measurement results demonstrate that it is highly feasible to seamlessly integrate the PACS networks into the Internet with global IP mobility and IP multicast services.  相似文献   

4.
Mobility support for Internet devices is quite important for consumer electronics. The number of the hand‐held devices is growing quickly. However, there are not enough IP addresses for the number of the rapidly growing devices in the All‐IP generation. Internet Protocol version 6 (IPv6) was therefore adopted to solve these problems. Our purposed structure is based on IEEE 802.11. However, IEEE 802.11 has a serious security drawback. Further, from the Internet Service Providers' point of view, accounting is a potential problem. A mechanism combining Mobile IPv6 and AAA based on IEEE 802.11 to overcome these problems is essential. Both Internet Protocol version 4 (IPv4) and IPv6 support IP security (IPsec) when data packets are exchanged across the IP network. IPsec operates at the IP layer. It can support system authentication and authorization, However, it lacks a system accounting function. Therefore ISPs cannot establish correct billing for their services. This is the reason why we chose to combine the wireless network and AAA functions. In this paper, the AAA mechanism is used to protect security, with the architecture having authentication, authorization, and accounting functions. We will discuss the benefits of AAA and state the reason why we choose to combine AAA with the mobility architecture. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

5.
Third-generation cellular networks have been designed to provide a variety of IP data services. Both IPv4 and IPv6 are supported in order to provide future-proof solutions. Mobility is supported through both cellular-specific and IP mechanisms. Mobile IP is becoming a key technology for managing mobility wireless networks. At the same time, the session initiation protocol is the key to realizing and provisioning services in IP-based cellular networks. The need for mobility of future real-time service independent of terminal mobility requires SIP to seamlessly interwork with mobile IP operations. In this article, we investigate the issues related to interworking between SIP and mobile IP, with a focus on IPv6 and the applicability to 3G networks being standardized in 3GPP and 3GPP2.  相似文献   

6.
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   

7.
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   

8.
In any Distributed Denial of Service (DDoS) attack, invaders may use incorrect or spoofed Internet Protocol (IP) addresses in the attacking packets and thus disguise the actual origin of the attacks. This is primarily due to the stateless nature of the Internet. IP traceback algorithms provide mechanisms for identifying the true source of an IP datagram on the Internet ensuring at least the accountability of cyber attacks. While many IP traceback techniques have been proposed, most of the previous studies focus and offer solutions for DDoS attacks done on Internet Protocol version 4 (IPv4) environment. IPv4 and IPv6 networks differ greatly from each other, which urge the need of traceback techniques specifically tailored for IPv6 networks. In this paper, we propose a novel traceback architecture for IPv6 networks using Common Open-Policy Service and a novel packet-marking scheme. We also provide complete underlying protocol details required for traceback support in IPv6 networks. The proposed architecture is on demand and only single packet is required to traceback the attack.  相似文献   

9.
Braun  T. 《Multimedia, IEEE》1997,4(3):85-90
Surveys recent and current standardization work by the Internet Engineering Task Force (IETF) on Internet communication protocols. The author describes the IPng project and the IPv6 protocol that will form the basis for upper-layer protocols such as resource reservation, transport and application level protocols. The IETF decided in 1992 to develop a new version of the Internet Protocol (IP) because the available address space of IP version 4 (IPv4) will probably run out early in the 21st Century. The need for a new IP version provided the opportunity to redesign the protocol and add new functions  相似文献   

10.
Intelligent Handoff for Mobile Wireless Internet   总被引:6,自引:0,他引:6  
This paper presents an intelligent mobility management scheme for Mobile Wireless InterNet – MWIN. MWIN is a wireless service networks wherein its core network consisting of Internet routers and its access network can be built from any Internet-capable radio network. Two major standards are currently available for MWIN, i.e., the mobile IP and wireless LAN. Mobile IP solves address mobility problem with the Internet protocol while wireless LAN provides a wireless Internet access in the local area. However, both schemes solve problems independently at different layers, thereby some additional problems occur, e.g., delayed handoff, packet loss, and inefficient routing. This paper identifies these new problems and performs analyses and some real measurements on the handoff within MWIN. Then, a new handoff architecture that extends the features of both mobile IP and wireless LAN handoff mechanism was proposed. This new architecture consists of mobile IP extensions and a modified wireless LAN handoff algorithm. The effect of this enhancement provides a linkage between different layers for preventing packet loss and reducing handoff latency. Finally, some optimization issues regarding network planning and routing are addressed.  相似文献   

11.
Gyasi-Agyei  A. 《IEEE network》2001,15(6):10-22
Realistic realization and mass acceptance of mobile data services require networking architectures offering acceptable quality of service and attractive tariffs. A novel strategy for this goal is maximum integration of popular data networking standards and their infrastructure into wireless networks. This article discusses a Mobile IP-based network architecture to provide IP services in DECT to support IMT-2000 applications. DECT offers micromobility within multicell subnets, while Mobile IP supports macromobility between multicell subnets. Incorporating Mobile IP into the DECT handoff mechanism in this way extends DECT micromobility with IP macromobility. Also, utilizing fast, seamless DECT handoff management reduces Mobile IP handoff delay to circumvent TCP throughput degradation during handoff and reduce frequency of Mobile IP signaling over the ether to conserve spectral efficiency. This feature seamlessly unifies DECT with the global Internet. Seamless integration of DECT with the Internet is crucial due to the continuing phenomenal popularity of the Internet and wireless communications, and ubiquity of DECT systems. To achieve the above DECT/IP interworking efficiently, the architecture introduces a network entity called a DECT service switching point, which is an extended DECT central control fixed part. DECT network-level services are mapped onto those of the IETF integrated services architecture to maintain QoS provided by DECT in the backbone Internet. Mobile Resource Reservation Protocol, an extended RSVP tailored to mobile networking, is adopted to provide the needed signaling in IntServ. The proposed architecture preserves traditional non-IP based services such as PSTN voice  相似文献   

12.
The ability of offloading selected IP data traffic from 3G to WLAN access networks is considered a key feature in the upcoming 3GPP specifications, being the main goal to alleviate data congestion in cellular networks while delivering a positive user experience. Lately, the 3GPP has adopted solutions that enable mobility of IP-based wireless devices relocating mobility functions from the terminal to the network. To this end, the IETF has standardized Proxy Mobile IPv6 (PMIPv6), a protocol capable to hide often complex mobility procedures from the mobile devices. This paper, in line with the mentioned offload requirement, further extends PMIPv6 to support dynamic IP flow mobility management across access wireless networks according to operator policies. Considering energy consumption as a critical aspect for hand-held devices and smart-phones, we assess the feasibility of the proposed solution and provide an experimental analysis showing the cost (in terms of energy consumption) of simultaneous packet transmission/reception using multiple network interfaces. The end-to-end system design has been implemented and validated by means of an experimental network setup.  相似文献   

13.
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   

14.
Mobile ATM offers a common wired network infrastructure to support mobility of wireless terminals, independent of the wireless access protocol. In addition, it allows seamless migration to future wireless broadband services, such as wireless ATM, by enabling mobility of end-to-end ATM connections. In spite of the diversity in mobile networking technologies (e.g., cellular telephony, mobile-IP, packet data services, PCS), all of them require two fundamental mechanisms: location management and handoff. This article describes different schemes for augmenting a wired ATM network to support location management of mobile terminals and handoff protocols for rerouting a connection data path when the endpoint moves. A prototype implementation of mobile ATM integrating mobility support with ATM signaling and connection setup, is presented. It shows how mobile ATM may be used to provide mobility support to an IP terminal using non-ATM wireless access  相似文献   

15.
IPv6对域名系统的需求及其解决方法的研究   总被引:3,自引:0,他引:3  
IPV6协议是取代IPV4的下一代网络协议,它具有许多新的特性与功能。域名系统(DNS)是Internet的基础架构,IPV6的新特性也需要DNS的支持,因此,DNS势必要升级以满足IPV6的需求,文章从IPV6的地址空间,IPV6地址自动配置和即插即用,IPV6的移动性,IPV4到IPV6的过渡等几方面对IPV6对DNS的需求及其解决方法进行了分析和研究。  相似文献   

16.
IP-based wireless networks will become the core of next-generation mobile networks. Mobility support plays an important role in all IP-based wireless networks for providing multimedia applications. In this article we address various major issues in mobility support for IP-based networks. Existing technology, including Mobile IP, Mobile IPv6, and other related techniques, are discussed. The issues of mobility support for wireless LANs, wireless WANs, 2-3G cellular networks, and next-generation heterogeneous mobile networks are also addressed in this article.  相似文献   

17.
为了满足移动式计算机用户对Internet移动接入需求的急剧增长,Internet工程任务组设计了移动IP。本文介绍了移动IP协议的基本特点、工作原理、路由优化及安全性,并对移动IPv6和基于ATM的移动IP作了简单的分析。  相似文献   

18.
The success of the Internet has attracted more people to take part in network navigation. Numerous wireless-communication devices have rapidly evolved in the past decade. The demand for mobile communications is increasing and packet data services through Internet protocol (IP) networks have become a trend. To supply more IP addresses to network devices and improve network performance, a new IP version 6 (IPv6) was developed by the Internet Engineering Task Force in 1994. IPv6 supports certain features that make mobility management more efficient in mobile IP. A cellular architecture is needed to improve the communications quality and to reduce power consumption, both at the base and mobile stations. In a cellular environment, handoffs occur frequently. Reducing the defects caused by handoffs is extremely important in the mobile network environment. This is especially important for high-speed moving devices. In this paper, a handoff strategy called neighbor-assisted agent architecture, which takes advantage of the ad-hoc network to improve handoff performance, is proposed. Timing analytical and simulation results show that the proposed mechanism can provide a better solution than mobile IP for handoff breaks during high-speed movement.  相似文献   

19.
RSVP Extensions for Real-Time Services in Hierarchical Mobile IPv6   总被引:2,自引:0,他引:2  
The Mobile IPv6 (MIPv6) provides many great features, such as sufficient addressing space, mobility, and security; MIPv6 is one of the most important protocols for next generation mobile Internet. Simultaneously, with the rapid improvement of wireless technologies, the real-time multi-media IP services such as video on demand, videoconference, interactive games, IP telephony and video IP phone will be delivered in the near future. Thus, to furnish accurate QoS for real-time services is one of the most important thing in the next generation mobile Internet. Although RSVP, which is a resource reservation protocol, processes signaling messages to establish QoS paths between senders and receivers, RSVP was originally designed for stationary networks and not aware of the mobility of MNs. Therefore, this paper proposes a novel RSVP extension to support real-time services in Hierarchical Mobile IPv6 (HMIPv6) environments. For intra-site mobility, the concept of QoS Agent (QA) is proposed to handle the RSVP QoS update messages and provide the advanced reservation models for real-time services. For inter-site mobility, IP multicast can help to invite inter-site QAs to make pre-reservation and minimize the service disruption caused by re-routing the data path during handover. Simulation results show that the proposed scheme over HMIPv6 is more suitable for real-time services than the famous RSVP tunnel-based solution.  相似文献   

20.
Mobility management for VoIP service: Mobile IP vs. SIP   总被引:4,自引:0,他引:4  
Wireless Internet access has gained significant attention as wireless/mobile communications and networking become widespread. The voice over IP service is likely to play a key role in the convergence of IP-based Internet and mobile cellular networks. We explore different mobility management schemes from the perspective of VoIP services, with a focus on Mobile IP and session initiation protocol. After illustrating the signaling message flows in these two protocols for diverse cases of mobility management, we propose a shadow registration concept to reduce the interdomain handoff (macro-mobility) delay in the VoIP service in mobile environments. We also analytically compute and compare the delay and disruption time for exchanging signaling messages associated with the Mobile IP and SIP-based solutions.  相似文献   

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