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1.
The success of the Internet is largely ascribable to the packet-switching scheme, which, however, also presents major challenges. Having identified three missing links in the current Internet architecture based on our long-term experiences of designing and operating large-scale backbones, we put forward a new, but incrementally deployable, network scheme—address switching. The address switching has both the advantages of packet switching and circuit switching; it supplies the missing links in the current Internet architecture and can reform the Internet traffic. Our analysis, protocol design and experiments indicate that the address switching can greatly improve the quality of service (QoS), security and routing scalability of today’s Internet. So it can provide flexible, high-performance and “per-service” networking for the scientific research communities. Moreover, it can provide a fairer and more sustainable business model for the commodity Internet. Supported by the China Next Generation Internet Project (Grant No. CNGI-04-13-2T), and the National Basic Research Program of China (Grant No. 041710001)  相似文献   

2.
Manageability is an important feature of next generation Internet;management and monitoring of IPv6-based networks are proving a big challenge.While leveraging current IPv4-based SNMP management scheme to IPv6 networks' management need is necessary,it is more urgent to coin a new network management architecture to accommodate the scalability and extensibility requirements of next generation Internet management.The paper proposes a novel network management architecture,IMN(Internet Management Network),whi...  相似文献   

3.
This paper presents the definition of multi-dimensional scalability of the Internet architecture, and puts forward a mathematical method to evaluate Internet scalability based on a variety of constraints. Then, the method is employed to study the Internet scalability problem in performance, scale and service scalability. Based on the examples, theoretical analysis and experimental simulation are conducted to address the scalability issue. The results show that the proposed definition and evaluation method of multi-dimensional Internet scalability can effectively evaluate the scalability of the Internet in every aspect, thus providing rational suggestions and methods for evaluation of the next generation Internet architecture.  相似文献   

4.
IETF softwire unicast and multicast framework for IPv6 transition   总被引:2,自引:0,他引:2  
IPv6 protocol plays an important role in the next generation of Internet (NGI). It is expected that the elegant coexistence of IPv4 and IPv6 is the key point of IPv6 transition. To solve the transition problem, we propose a mesh unicast framework and a multicast framework in this paper. We describe two reference models for the mesh unicast framework, and put forward two potential solutions for the multicast framework. A Linux-based prototype is implemented for IPv4 over IPv6 scenario and a test bed is deployed with 8 nodes on CERNET2. The deployment demon- strates the advantages of the framework.  相似文献   

5.
In this paper, the algebraic operations on the cuts of lattice-valued regular languages are studied. Some sufficient conditions are given to guarantee the family of the cuts of lattice-valued regular languages to be closed under such algebraic operations as union, intersection, complement, quotient, homomorphism, inverse homomorphism, concatennation, reversal, etc. This work is supported by National Science Foundation of China (Grant No.10571112), “TRAPOYT” of China and National 973 Foundation Research Program (Grant No. 2002CB312200).  相似文献   

6.
SKY: efficient peer-to-peer networks based on distributed Kautz graphs   总被引:1,自引:0,他引:1  
Many proposed P2P networks are based on traditional interconnection topologies. Given a static topology, the maintenance mechanism for node join/departure is critical to designing an efficient P2P network. Kautz graphs have many good properties such as constant degree, low congestion and optimal diameter. Due to the complexity in topology maintenance, however, to date there have been no effective P2P networks that are proposed based on Kautz graphs with base > 2. To address this problem, this paper presents the “distributed Kautz (D-Kautz) graphs”, which adapt Kautz graphs to the characteristics of P2P networks. Using the D-Kautz graphs we further propose SKY, the first effective P2P network based on Kautz graphs with arbitrary base. The effectiveness of SKY is demonstrated through analysis and simulations. Supported partially by the National Natural Science Foundation of China (Grant Nos. 60673167 and 60703072), the Hunan Provincial Natural Science Foundation of China (Grant No. 08JJ3125), and the National Basic Research Program of China (973) (Grant No. 2005CB321801)  相似文献   

7.
A pure quasi-human algorithm for solving the cuboid packing problem   总被引:2,自引:0,他引:2  
We excavate the wisdom from an old Chinese proverb “gold corner, silver side and strawy void”, and further improve it into “maximum value in diamond cave” for solving the NP-hard cuboid packing problem. We extract, integrate and formalize the idea by west modern mathematical tools, and propose a pure quasi-human algorithm. The performance of the algorithm is evaluated on two sets of public benchmarks. For 100 strongly heterogeneous difficult benchmarks, experiments show an average packing utilization of 87.31%, which surpasses current best record reported in the literature by 1.83%. For 47 difficult benchmarks without orientation constraint, experiments show an average volume utilization of 92.05%, which improves current best record reported in the literature by 1.05%. Supported by the National Natural Science Foundation of China (Grant No. 60773194), the National Basic Research Program of China (Grant No. 2004CB318000), and Postdoctoral Science Foundation of China (Grant No. 20070420174)  相似文献   

8.
Intuitionistic fuzzy recognizers and intuitionistic fuzzy finite automata are discussed. The notions of intuitionistic fuzzy recognizer, complete accessible intuitionistic fuzzy recognizer, intuitionistic fuzzy finite automata, deterministic intuitionistic fuzzy finite automata, and intuitionistic fuzzy language are introduced. It is shown that the languages recognized by intuitionistic fuzzy recognizer are regular, and the intuitionistic fuzzy languages recognized by the intuitionistic fuzzy finite automaton and the intuitionistic fuzzy languages recognized by deterministic intuitionistic fuzzy finite automaton are equivalent. This work is supported by National Science Foundation of China (Grant No.10571112), “TRAPOYT” of China and National 973 Foundation Research Program(Grant No.2002CB312200).  相似文献   

9.
The foundation of any network management systems is a database that contains information about the network resources relevant to the management tasks.A network information model is an abstraction of network resources,including both managed resources and managing resources,In the SNMP-based management framework,management information is defined almost exclusively from a “Device“ viewpoint,namely managing a network is equivalent to managing a collection of individual nodes.Aiming at making use of recent advances in distributed computing and in object-oriented analysis and design,the Internet management architecture can also be based on the Open Distributed Processing Reference Model(RM-ODP).The purpose of this article is to provide an Internet Network Resource Information Model.First,a layered management information architecture will be discussed.Then the Internet Network resource information model is presented.The information model is specified using object-Z.  相似文献   

10.
一种基于哈希表和Trie树的快速IP路由查找算法   总被引:3,自引:0,他引:3  
Internet的飞速发展要求核心路由器每秒能转发几百万个以上的分组,实现高速分组转发的关键是路由表的组织和快速的路由查找算法。论文提出了一种基于8比特的前向查找表(LFT)和7比特的简单二进制回退查找Trie树(HBT)的IP路由查找算法。算法综合考虑了IP地址的分布特点,兼顾了查找速度、存储空间利用、硬件实现,以及向IPv6过渡等几个因素。具有算法简单、查找速度较快、存储空间利用率较高、易于扩展和便于硬件实现等特点。  相似文献   

11.
Bump mapping is a texture-based rendering approach for simulating surface details to make its illumination results have three-dimensional effects. The bumpy properties of an object are determined by height maps. But in the process of generating height maps, a problem arises, i.e. to get a correct value of the pixel height, empirical data should be calculated repeatedly, which proves very complicated, and meanwhile the realistic rendering effect is reduced, because the bumpy property is exaggerated in the height map. Therefore, in this paper, we present a method for describing the details of the bumpy texture, where a new concept “bumpy map” is introduced to replace the height map. Experimental results demonstrate that the bumpy details produced by the “bumpy map” are more consistent with the original bumpy texture than by the method of height map. Supported partially by the National Natural Science Foundation of China (Grant Nos. 60533030, 60825203, 60572104), National High-Tech Research & Development Program of China (Grant No.2006AA01Z317), Science and Technology Development Program of Education Commission in Beijing (Grant No. KM200710005017)  相似文献   

12.
基于层次寻址扩展IP网地址空间的研究   总被引:3,自引:0,他引:3  
为解决IP地址窀问耗尽问题,该文提出了一种分级寻址的IP网体系结构(IPEA),说明了分级寻址的IP网地址空间与寻址方案,定义了带扩展地址的IP包格式,及层次路由算法。并以仿真实验分析评价了IPEA的性能,结果表明IPEA有以下优点:(1)采用扩展地址扩大了地址空间,解决了IPv4地址耗尽问题;(2)减小了路由表长度。有利于解决路由表爆炸问题;(3)基本不改变IPv4寻址方式。迁移容易;(4)由于使用了内部地址,更便于网络管理。  相似文献   

13.
作者在融合物联网的新一代互联网网络环境下,提出了基于IPv6的源地址验证整体架构.基于该架构,考虑物联网节点资源受限特点,并结合物联网末梢网络的拓扑形态及其路由方式上的特征,设计了基于IPv6的物联网末梢网络分布式源地址验证方案.分别讨论了静态指定、SLAAC(Stateless Address AutoConfiguration)、DHCPv6(Dynamic Host Configuration Protocol Version 6)以及DHCPv6与SLAAC混合情况下的物联网节点IP地址分配及其验证机制.模拟实验表明,该方案仅以微小的代价实现了物联网节点IP地址的分配,同时还保证了物联网节点之间、物联网节点与互联网端系统之间端到端通信时双方IP地址的真实可靠性,从而整体上增强了物联网的安全性.  相似文献   

14.
A new generation architecture of IP routers called massive parallel forwarding and switching (MPFS) is proposed, which is totally different from modern routers. The basic idea of MPFS is mapping complicated forwarding process into multilevel scalable switch fabric so as to implement packet forwarding in a pipelining and distributed way. This processing mechanism is named forwarding in switching (FIS). By interconnecting multi-stage, lower speed components, called forwarding and switching nodes (FSN), MPFS achieves better scalability in forwarding and switching performance just like MPP. We put emphasis upon IPv6 lookup problem in MPFS and propose a method for partitioning IPv6 FIB and mapping them to switch fabric. Simulation and computation results suggest that MPFS routers can support line-speed forwarding with a million of IPv6 prefixes at 40 Gbps. We also propose an implementation of 160 Tbps core router based on MPFS architecture at last.  相似文献   

15.
An Effective Feedback Control Mechanism for DiffServ Architecture   总被引:1,自引:0,他引:1       下载免费PDF全文
As a scalable QoS(Quality of Service)architcture,DiffServ(Differentiated Service)mainly consists of two components:taffic conditioning at the edge of the DiffServ domain and simple packet forwarding inside the DiffServ domain.DiffServ has many advantages such as flexbility,scalability and simplicity.But when providing, AF (Assured Forwarding) services ,DiffServ has some problems such as unfairness among aggregated flows or among micro-flows belonging to an aggregated flow.In this paper,a feedback mechanism for AF aggregated flows is proposed to solve this problem.Simulation results show that this mechanism does improve the performance of DiffServ.Firt,it can improve the fairness among aggregated flows and make DiffServ more friendly toward TCP (Transmision Control Protocol)flows.Second,it can decrease the buffer requirements at the congested router and thus obtain lower delay and packet loss rate.Third,it also keeps almost the same link utility as in normal DiffServ,Einally,it is simple and easy to be implemented.  相似文献   

16.
Computational similarity measures have been evaluated in a variety of ways, but few of the validated computational measures are based on a high-level, cognitive criterion of objective similarity. In this paper, we evaluate two popular objective similarity measures by comparing them with face matching performance in human observers. The results suggest that these measures are still limited in predicting human behavior, especially in rejection behavior, but objective measure taking advantage of global and local face characteristics may improve the prediction. It is also suggested that human may set different criterions for “hit” and “rejection” and this may provide implications for biologically-inspired computational systems. Supported by the National Basic Research Program of China (Grant No. 2006CB303101), the National Natural Science Foundation of China (Grant Nos. 60433030, 30600182 and 30500157), and the Royal Society  相似文献   

17.
Parallel Error Detection for Leading Zero Anticipation   总被引:1,自引:0,他引:1       下载免费PDF全文
The algorithm and its implementation of the leading zero anticipation (LZA) are very vital for the performance of a high-speed floating-point adder in today's state of art microprocessor design. Unfortunately, in predicting "shift amount" by a conventional LZA design, the result could be off by one position. This paper presents a novel parallel error detection algorithm for a general-case LZA. The proposed approach enables parallel execution of conventional LZA and its error detection, so that the error-indicatlon signal can be generated earlier in the stage of normalization, thus reducing the critical path and improving overall performance. The circuit implementation of this algorithm also shows its advantages of area and power compared with other previous work.  相似文献   

18.
This paper presents a network-based analysis approach for the reconfiguration problem of a self-reconfigurable robot. The self-reconfigurable modular robot named "AMOEBA-I" has nine kinds of non-isomorphic configurations that consist of a configuration network. Each configuration of the robot is defined to be a node in the weighted and directed configuration network. The transformation from one configuration to another is represented by a directed path with nonnegative weight. Graph theory is applied in the reconfiguration analysis, where reconfiguration route, reconfigurable matrix and route matrix are defined according to the topological information of these configurations. Algorithms in graph theory have been used in enumerating the available reconfiguration routes and deciding the best reconfiguration route. Numerical analysis and experimental simulation results prove the validity of the approach proposed in this paper. And it is potentially suitable for other self-reconfigurable robots' configuration control and reconfiguration planning.  相似文献   

19.
提出了一种下一代互联网中移动自组网的移动管理方案。此方案提出了与IPv6网络体系结构充分融合的基于簇的MANET层次体系结构,并提出了簇的建立算法,实现了簇首节点数量最小化。基于所提的MA-NET层次体系结构,提出了MANET节点的IPv6地址分层结构以及相应的IPv6地址配置算法。基于所提的MA-NET层次体系结构以及IPv6地址分层结构,提出了移动自组网移动管理方案。分析结果验证了本方案有效减少了移动转交次数,降低了控制信息代价以及数据包丢失率。  相似文献   

20.
IPv6作为下一代物联网IP层技术,进一步扩大了地址空间,并在国家政策的号召以及国家电网公司的积极响应下在电力、石油等方面获得了广泛的应用,为智能电网与下一代互联网的深度融合探索道路、提供经验。但是其应用中仍然存在较多重大的问题,其中最为突出的就是其安全性和真实性。当前的网络体系结构,大多数情况下并不检查源地址,这就导致源地址伪造事件很容易发生。本文主要分析了物联网对IPv6的需求,总结了多种IPv6源地址验证方案,并重点对SAVS框架下的IPv6源地址验证方案进行分析和探讨。  相似文献   

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