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1.
In this article, we propose a dynamic Internet Protocol (IP) address assignment architecture for heterogeneous wireless IP devices network. The IP device could be a sensor device, a laptop, a cell phone, or any wireless device using IP communications. The proposed architecture introduces security and service reliability to the consumer while reducing the operational expenditure for the service providers. According to the proposed scheme, each node maintains an IP address pool storing the current occupancy of each IP address. Each node advertises its database whenever the ratio of negative acknowledgments from the domain name server to the total number of requests at a given node exceeds a certain threshold. We evaluate our IP assignment scheme under two traffic intensity scenarios, namely the uniform traffic intensity and the heterogeneous traffic intensity. Performance evaluation is carried out with respect to blocking probability and average IP list utilization. We define three types of blocking probability for the user requests as follows: The real blocking, the unjustified acceptance, and the unjustified rejection. We observe that the proposed scheme outperforms the uniform assignment as long as the threshold is below 1.5% for the uniform intensity scenario and 1% for the heterogeneous scenario. Furthermore, this architecture considers the security aspect of the wireless network by allowing only registered devices to communicate with other registered devices. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

2.
QoS issues in the converged 3G wireless and wired networks   总被引:5,自引:0,他引:5  
The Internet evolution delineated through the last years has urged the wireless network community to support the deployment of IP multimedia services with guaranteed quality of service (QoS) in 3G wireless networks. This article copes with the interoperability between 3G wireless networks and wired next-generation IP networks, for the provision of services with an a priori known quality level over both environments. More specifically, the UMTS architecture as well as a prototypical implementation of the next-generation Internet based on DiffServ are considered. The article focuses on the mapping among the traffic classes of the two networks at the point where the networks converge, and discusses the requirements and possible solutions for their proper interworking at the signaling and user levels. Simulations prove that proper mapping among the traffic classes of each world is necessary in order to achieve the desired end-to-end traffic characteristics.  相似文献   

3.
Extending Global IP Connectivity for Ad Hoc Networks   总被引:1,自引:0,他引:1  
Ad hoc networks have thus far been regarded as stand-alone networks without assumed connectivity to wired IP networks and the Internet. With wireless broadband communications and portable devices with appropriate CPU, memory and battery performance, ad hoc connectivity will become more feasible and demand for global connectivity through ad hoc networking is likely to rapidly grow. In this paper we propose an algorithm and describe a developed prototype for connectivity between an ad hoc network running the ad hoc on-demand distance-vector protocol and a wired IP network where mobile IP is used for mobility management. Implementation issues and performance metrics are also discussed.  相似文献   

4.
合理构筑宽带IP网的骨干网   总被引:1,自引:0,他引:1  
房建成 《世界电信》1999,12(9):12-14
在IP业务的冲击下对下一代IP网络方案的讨论如火如荼。本文在对各种方案 本介绍的基础上,对IPoverATM和IPoverSDH两种方案进行了比较。前者在QoS、多业务支持及带宽管理方面具有优势2,而后者的带宽利用率较高,且组网简单。前者地传统电信运营商的网络,后者则对所新兴的IP业务运营商更为有利。  相似文献   

5.
Trends in fourth generation (4G) wireless networks are clearly identified by the full-IP concept where all traffic (data, control, voice and video services, etc.) will be transported in IP packets. Many proposals are being made to enhance IP with the functionalities necessary to manage the mobility of nodes, so that networks can provide global seamless roaming between heterogeneous wireless and wired networks. In this paper, we focus on the management of universal mobility, including both large scale macro-mobility and local scale micro-mobility. We propose a hierachical architecture (i) extending micro-mobility management of a wireless access network to an ad-hoc access network, (ii) connecting this ad-hoc network to the Internet and (iii) integrating Mobile IP and OLSR, a routing protocol for ad-hoc networks, to manage universal mobility. This architecture is validated by an implementation based on DynamicsMobile-IP and OLSR version 7. We show how the brodcast of Mobile-IP Agent Advertisement can be optimized using OLSR MPR-flooding.  相似文献   

6.
This paper deals with quality of service (QoS) provision in wireless IP networks. QoS provision is particularly challenging in wireless networks, where network resources are generally limited, variable over time and shared. In the design of possible measures to assure QoS one should consider that standardization is well established for the network layer Internet Protocol and for many underlying technologies of frequent use (e.g. IEEE 802.11, BLUETOOTH or HIPERLAN II). Therefore, as far as research on QoS is concerned, there is little room in both the IP and the link-layers for improved IP over wireless interfaces. In this paper we illustrate a solution in which an intermediate Wireless Adaptation Layer (WAL) is transparently interposed between the IP layer and specific link-layer technologies as a solution to provide QoS. The WAL addresses two main issues: (i) compensation for channel impairments in different platforms in order to enhance wireless channel reliability and (ii) implementation of traffic control and packet scheduling mechanisms to satisfy bandwidth and delay requirements, as well as to enforce a general principle of fairness among the IP associations contending for network resources and achieve optimal exploitation of transmission capacity. The WAL consists of a set of modules, each one in charge of a specific task, which can be enabled or disabled depending on the specific network environment. The novelty of the WAL approach is its capability of adapting itself to different wireless interfaces selecting performance enhancing modules for specific networks. This requires to modify the standard TCP/IP protocol stack by introducing an intermediate layer between the IP layer and the Data Link layer, with performance enhancement purposes. This paper focuses on two modules in particular, namely a traffic control module, which is in charge of performing congestion control and channel state dependent scheduling (CSD) packet scheduling, and a forward error correction (FEC) module, which compensates for channel impairments. This paper presents the proposed architecture provided with these modules and reports some measurements and simulations highlighting benefits resulting from the use of such modules.  相似文献   

7.
With the advent of IP technologies and the tremendous growth in data traffic, the wireless industry is evolving its core networks toward IP technology. Enabling wireless Internet access is one of the upcoming challenges for mobile radio network operators. The General Packet Radio Service is the packet-switched extension of GSM and was developed to facilitate access to IP-based services better than existing circuit-switched services provided by GSM. We illustrate how a visited mobile subscriber on a GPRS/UMTS network can access his/her home network via the gateway GPRS support node (GGSN). We also propose some implementation ideas on wireless Internet access for a remote mobile subscriber based on a GPRS/UMTS network  相似文献   

8.
移动IP的预测移动管理   总被引:2,自引:0,他引:2  
移动IP使移动主机在移动中能够接入Internet而不中断正在的连接,但移动IP的切换时延较大,不能保证业务的平滑切换,本文提出了层次和预测移动管理的方法,结合无线域内的邻居单播,取得了移动IP的快速和平滑的切换,改善了业务的QOS,并减少了无线域内有线网络的负担。  相似文献   

9.
Wireless sensor networks (WSNs) are composed of thousands of smart‐sensing nodes, which capture environment data for a sink node. Such networks present new challenges when compared with traditional computer networks, namely in terms of smart node hardware constraints and very limited energy resources. Ubiquitous computing can benefit from WSNs from the perspective that sensed data can be used instead of the user without explicit intervention, turning ubiquitous computing into a reality. Internet connectivity in WSNs is highly desirable, featuring sensing services at a global scale. Two main approaches are considered: proxy based or sensor node stack based. This second approach turns sensors into data‐producing hosts also known as ‘The Internet of Things’. For years, the TCP/IP (Transmission Control Protocol/Internet Protocol) suite was considered inappropriate for WSNs, mainly due to the inherent complexity and protocol overhead for such limited hardware. However, recent studies made connecting WSNs to the Internet possible, namely using sensor node stack based approaches, enabling integration into the future Internet. This paper surveys the current state‐of‐the‐art on the connection of WSNs to the Internet, presents related achievements, and provides insights on how to develop IP‐based communication solutions for WSNs today. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

10.
新3G系统——无线移动因特网   总被引:1,自引:0,他引:1  
本文提出一种新3G系统,这种新3G系统立足于3G框架之内,使用3G的工作频率,采用现有的技术实现具有IMT-2000以后系统特征的宽带无线移动因特网系统。运营商可以利用其已有的固定宽带因特 资源建设发展宽带无线移动因特网,并且可以以极低成本在其上提供新话音和多媒体业务,我国发展新3G系统将引领世界宽带无线移动因特网发展潮流。  相似文献   

11.
吴渭  吴滨 《无线电通信技术》2007,33(2):12-13,64
针对服务质量(QoS)保证技术问题,从移动性、无线链路特性和IP网络传统的QoS保证技术的改进几个方面出发,对下一代支持多种移动无线接入的IP网络中,QoS保证技术的相关研究热点及技术现状进行了分析和总结,并提出了本研究方向QoS分层模型和进一步的研究建议。  相似文献   

12.
Toward a new IP over ATM routing paradigm   总被引:1,自引:0,他引:1  
The explosive growth of the Internet has given IP routing new challenges. Innovative solutions have been proposed to solve the current router bottleneck by evolving to a tighter integration of IP and ATM, an approach called shortcut routing. This article categorizes the current IP over ATM shortcut proposals and identifies a number of issues. However, while IP and ATM routing and forwarding functions must be more closely integrated, a differentiation according to type of traffic seems advantageous; hence the need to evolve to an IP over ATM dual-mode routing model  相似文献   

13.
3G无线网络的IP技术研究   总被引:1,自引:0,他引:1  
论述了当前主要研究的支持3G无线网络的IP技术、移动IP、蜂窝IP、HAWAII和TeleMIP,并对它们进行了比较分析,总结了当前的无线IP技术的特点和发展趋势。  相似文献   

14.
Architecture and Engineering Issues in Building an IP over WDM Networks   总被引:1,自引:0,他引:1  
The technologies of IP over WDM have presently received increasing attention owing to the rapid growth in Internet traffic and the need for next-generation Internet technologies. The challenge now is how to integrate the services of IP over WDM optical networks to take full advantages of WDM technologies and IP technologies, and yield a high-throughput optical platform directly underpinning next generation data networks. This article discusses some of the architecture and technology issues for the design of IP over WDM optical networks.  相似文献   

15.
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   

16.
移动IP路由优化性能分析及仿真   总被引:17,自引:0,他引:17       下载免费PDF全文
裴珂  李建东  郭峰 《电子学报》2002,30(4):484-487
因特网技术的普及,使得人们实现了网际通信和信息共享,但基于有线方式的Internet受到空间和时间的限制,无法满足用户随时随地能够接入因特网的要求,这成为研究移动主机路由协议的驱动力.移动IP是一种简单、可扩展的全球IP移动性的解决方案,但三角路由问题的存在带来了网络花费问题和性能问题.路由优化移动IP协议是解决移动IP相关问题的侯选协议之一.本文对两种协议进行了理论分析和仿真.结果表明,是否采用路由优化协议,不能一概而论,要根据网络及业务到达特征决定.另外,两种协议都不能很好地支持将来的微小区带来的频繁切换,而解决该问题就是我们下一步的研究方向.  相似文献   

17.
Internet performance monitoring   总被引:4,自引:0,他引:4  
The growing diversity of services in the Internet is motivating research to improve measurability of traffic and Internet performance. This paper surveys current projects and tools for Internet performance monitoring, ranging from passive router-based traffic flow measurement methods to large-scale active performance monitoring projects. The tools and methods are discussed according to their protocol layer, starting from the network layer (ATM, MPLS) to IP/ICMP and transport/application layers. At each protocol layer the strengths and limitations of the methods are highlighted. Finally, issues and challenges for future research are reviewed  相似文献   

18.
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   

19.
张薇 《电子世界》2012,(21):4-5
随着IP技术的迅速渗透和无线数据业务的高速增长,无线业界一致决定将3G核心网朝着全IP方向发展。本文提出了基于IP承载技术的软交换汇接网和网管组网方案,此方案提升了网络的利用率和网络投资的效益,充分发挥了软交换和IP承接网络技术的优势,满足了中远期业务发展的需要。  相似文献   

20.
桂林卿  罗汉文 《通信技术》2007,40(9):42-43,48
目前广泛使用的因特网协议(IP)已经成为所有数据业务的传输标准。传统的因特网业务策略(BE策略)不能满足新兴的实时业务的需求,因此有必要引入IPQoS机制来更有效的分配资源。由于第三代通信系统网UMTS需要同时支持非实时和实时业务,而且无线网的资源和设备比固定网昂贵得多,所以IPQoS机制对于无线网络尤为重要。文中首先研究因特网IPQoS机制,然后讨论如何将其应用到UMTS网络中。  相似文献   

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