共查询到20条相似文献,搜索用时 125 毫秒
1.
间断连接网络中通常是利用多副本数据转发方式来提高数据成功投递概率;但多副本的数据转发易导致冗余数据副本出现的频率升高。对此,设计了动态获知节点状态的间断连接网络拥塞控制机制(SCCS,State-aware Congestion Control Strategy)。引入平滑数学模型,结合节点间的相遇历史信息,构造了效用函数,从而以间接获知网络信息的方式预测下一时刻网络的拥塞情况,进而以分布式的方式动态选择较为合适的中继节点,以更加合理地利用有限的网络资源。仿真结果表明:与当前性能较好的拥塞控制机制相比,该机制的数据成功投递概率更高,而网络负载率更低。 相似文献
2.
3.
4.
《电子与信息学报》2016,38(2):310-317
间断连接无线网络利用节点移动产生的通信机会完成数据传输,但网络中的恶意节点通过伪造节点的相遇信息等方法,吸引并丢弃数据,影响网络的运行。该文提出带有黑洞攻击探测的间断连接无线网络数据转发机制,通过节点诚信度、信用度、间接信任度及数据转发能力4维信任属性的评估,获知攻击节点的行为规律,并采用粗糙集理论降低网络运行过程中产生的不确定状态信息引发的误判率,更加准确地对节点的可信性进行判断,进而,合理地为数据选择中继节点。结果表明,所提出的方法能有效提升黑洞节点的辨识率,对网络中其它非协作行为也有一定探测和防御能力,能显著改善网络性能。 相似文献
5.
内容中心网络状态感知路由设计 总被引:1,自引:0,他引:1
为了提高内容中心网络的内容分发效率及降低网络开销,提出了网络状态感知的路由机制NSAR(network status aware routing)。NSAR利用从内容服务节点返回的数据分组收集当前网络状态信息,并在回传过程中对路径上各节点上匹配端口的转发概率进行更新,在对后续的兴趣分组进行转发决策时引入转发概率,从而提高内容分发效率。仿真实验表明,与传统内容中心网络路由算法相比,NSAR可以有效地降低内容请求平均时延,减少网络流通分组数以及降低网络带宽开销。 相似文献
6.
7.
8.
网络编码方法能有效提高数据传输效率,但采用该方法的机会网络数据转发机制均未考虑传输中的编码数据迭代冗余副本控制问题。为了充分降低译码复杂度并减少迭代冗余副本,提出了相遇持续时间估计及编码机会感知方法,进而设计了带有传输容量估计的编码冗余控制数据转发机制。节点以分布式的方式感知数据编码机会,为不同扩散程度的数据确定相应的优先级,并根据传输容量估计结果完成转发控制,以充分利用节点间的相遇持续时间。结果表明,所提出机制有效地减少了网络中的冗余副本,使译码所需的数据量趋于理论上的最小值,改善了网络资源利用率。 相似文献
9.
10.
11.
Non-center network computing environments have some unique characteristics, such as instability, heterogeneity, autonomy, distribution and openness, which bring serious issues of security and reliability. This article proposes a brand-new credibility protection mechanism for resource sharing and collaboration in non-center network computing environments. First, the three-dimensional hierarchical classified topology (3DHCT) is proposed, which provides a basic framework for realizations of the identity credibility, the behavior credibility and the capability credibility. Next, the agent technology is utilized to construct the credibility protection model. This article also proposes a new comprehensive credibility evaluation algorithm with simple, efficient, quantitative and able to meet the requirements of evaluating behavior credibility and the capability credibility evaluation as well. The Dempster-Shafer theory of evidence and the combination rule are used to achieve the evaluation of the capability credibility. The behavior credibility is evaluated with the current and historical performance of nodes for providers and consumers to realize more accurate prediction. Based on the non-center network computing simulation test platform, simulation is been conducted to test the performance and validity of the proposed algorithms. Experiment and analysis show that the proposed algorithms are suitable for large-scale, dynamic network computing environments, and able to maintain the credibility for networks without relying on central node, make a non-center network gradually evolve into an orderly, stable and reliable computing environment efficiently. 相似文献
12.
13.
杜风雷 《微电子学与计算机》2012,29(3):129-132
提出一种局部信誉度模型计算P2P网络的信誉度.根据网络节点之间的交易记录,计算系统的时间和空间开销,依据系统开销最小的原则从网络节点中选取多个局部中心节点,来替代传统的集中式模型中的单一中心节点,完成系统的信誉度计算,这样就避免了传统的集中式模型中心节点计算量大、耗时长的问题.实验证明,这种方法能够减少信誉度计算的耗时,提高计算的实时性,及时有效地保护了网络的安全. 相似文献
14.
基于证据相似性度量,该文提出一种冲突性区间证据融合的新方法。首先,定义了扩展型Pignistic概率转换,将区间证据转换为区间型Pignistic概率。利用区间模糊集的归一化欧式距离,求取区间型Pignistic概率之间的相似性,以此确定两两证据间的相似度矩阵,从中获取区间证据的置信度。然后,基于该置信度对原始的区间证据进行加权平均得到新的区间证据,利用Demspter区间证据组合公式对其进行融合。该方法可以有效地减弱高冲突性区间证据在组合规则中的作用,从而减小融合后所得区间证据的宽度,最终可降低决策中的不确定性。最后通过多个典型算例验证了经冲突处理后再对区间证据进行融合,要比直接融合能够产生更为合理和可靠的结果。 相似文献
15.
The vast literature on the wireless sensor research community contains many valuable proposals for managing energy consumption, the most important factor that determines sensors’ lifetime. Interesting researches have been facing this requirement by focusing on the extension of the entire network lifetime: either by switching between node states (active, sleep) or by using energy-efficient routing. We argue that a better extension of the network lifetime can be obtained if an efficient combination of management mechanisms can be performed at the energy of each single sensor and at the load distribution over the network. Considering these two accuracy levels (i.e., node and network), this paper presents a new approach that uses cost functions to choose energy-efficient routes. In particular, by making different energy considerations at a node level, our approach distributes routing load, avoiding, thus, energy-compromised hotspots that may cause network disconnections. The proposed cost functions have completely decentralized and adaptive behavior and take into consideration the end-to-end energy consumption, the remaining energy of nodes, and the number of transmissions a node can make before its energy depletion. Our simulation results show that, though slightly increasing path lengths from sensor to sink nodes, some proposed cost functions (1) improve significantly the network lifetime for different neighborhood density degrees, while (2) preserving network connectivity for a longer period of time. 相似文献
16.
17.
18.
19.
为了有效提高分布式传感器网络中航迹与航迹关联的计算速度,本文提出了一种新的基于临时航迹和信源相对可信度的多源模糊航迹关联算法。该算法首先在全局融合中心利用来自同一局部融合节点的同一航迹的两个量测形成临时航迹,再由临时航迹与系统航迹融合生成系统航迹,航迹关联是在临时航迹与系统航迹间进行的;并引入信源相对可信度,当有多条临时航迹与系统航迹关联时,选取信源相对可信度最大的临时航迹与系统航迹关联。将该算法用于一个多源航迹关联的仿真实验中,仿真结果表明该算法在保证关联正确率的前提下,与传统的模糊航迹关联算法相比,进一步提高了航迹关联的计算速度和系统航迹的精度,是一种有效的多源航迹关联方法。 相似文献