检索结果-南通市图书馆

Scalable Security Solution Against Wiretapping for Network Coding Based Priority Encoding Transmission

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2018年第1期27卷 191-197页

作者： liu guangjun XIAO Song School of Information Engineering Xi'an University School of Telecommunication Engineering Xidian University

Network coding is promising to improve the throughput and robustness of video transmission over wireless networks. To address the security issue of network coding based Priority encoding transmission(PET), a special coding design against wiretapping is proposed with hierarchical security. The basic idea is first to randomize partial blocks of each layer and then to encode each layer with inter-layer overlapping coding. The method is characterized by quantifiable security for incremental decoding,and realizes scalability in confidentiality and video transmission, while incurring relatively low computational complexity and bandwidth overhead. A sufficient condition is also presented to design a stronger secure network coded PET system against the known-plaintext attacks. Analysis and evaluation show that the method can be efficient as a new paradigm to secure network coded PET system in realistic applications.

关键词： Network coding Hierarchical confidentiality Priority encoding transmission(PET) Video streaming

Security Analysis and Improvement of a Tag Encoding Authentication Scheme for Network Coding

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2016年第5期21卷 394-398页

作者： liu guangjun School of Information Engineering Xi'an University

A tag encoding authentication scheme for network coding proposed by Wu et al was claimed to defend pollution attacks efficiently. However, we find that the scheme easily incurs multi-generation pollution attacks, where an adversary may be able to recover the main secret key of the source with high probability during multi-generation transmitting, and the scheme also cannot resist against inter-generation pollution attacks. Using a dynamic source secret key technology that the key can be updated with the change of generation identifier, an improved scheme is then presented, which can counteract these security defects without any efficiency compromise.

关键词： network coding pollution attack inter-generation pollution attack multi-generation pollution attack

Low-Complexity Secure Network Coding Against Wiretapping Using Intra/Inter-generation Coding

在线全文

学校读者我要写书评

暂无评论

China Communications 2015年第6期12卷 116-125页

作者： liu guangjun liu Binyue liu Ximeng LI Fang GUO Wangmei School of Information Engineering Xi'an University State Key Laboratory of Integrated Service Networks Xidian University

Existing solutions against wiretapping attacks for network coding either bring significant bandwidth overhead or incur a high computational *** order to reduce the security overhead of the existing solutions for securing network coding,a novel securing network coding paradigm is presented relying on two coding models:intra-generation coding and inter-generation *** basic idea to secure network coding using intra-generation coding is to limit the encryption operations for each generation,and then subject the scrambled and the remaining original source vectors to a linear *** method is then generalized seamlessly using inter-generation coding by further exploiting the algebraic structure of network *** show that the proposed schemes have properties of low-complexity security,little bandwidth consumption,and high efficiency in integrating with the existing security techniques effectively.

关键词：网络编码安全性能低复杂度帧间编码窃听带宽控制计算复杂度编码模式

Methanol steam reforming for hydrogen production driven by an atomically precise Cu catalyst

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2024年第7期9卷 1079-1084页

作者： Weigang Hu Haoqi liu Yuankun Zhang Jiawei Ji guangjun Li Xiao Cai Xu liu Wen Wu Xu Weiping Ding Yan Zhu School of Chemistry and Chemical Engineering Nanjing University School of Physical Science and Technology Ningbo University

Plasmon-induced hot-electron transfer from metal nanostructures is being intensely pursed in current photocatalytic research,however it remains elusive whether molecular-like metal clusters with excitonic behavior can be used as light-harvesting materials in solar energy utilization such as photocatalytic methanol steam *** this work,we report an atomically precise Cu13cluster protected by dual ligands of thiolate and phosphine that can be viewed as the assembly of one top Cu atom and three *** Cu13H10（SR）3（PR’3）7(SR=2,4-dichlorobenzenethiol,PR’3=P（4-FC6H4）3) cluster can give rise to highly efficient light-driven activity for methanol steam reforming toward H2production.

关键词： Nanocluster Photocatalysis Methanol steam reforming Atomically precise Copper catalyst

Matroidal Error Correction Networks and Linear Network Error Correction MDS Codes

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2013年第6期18卷 477-483页

作者： ZHOU Hang liu guangjun The State Key Laboratory of Integrated Services Networks Xidian University College of Science Engineering University of the Chinese People's Armed Police Force School of Mathematics and Computer Engineering Xi'an University of Arts and Science

In this paper, we further study the connections between linear network error correction codes and representable matroids. We extend the concept of matroidal network introduced by Dougherty et al. to a generalized case when errors occur in multi- ple channels. Importantly, we show the necessary and sufficient conditions on the existence of linear network error correction mul- ticast/broadcast/dispersion maximum distance separable （MDS） code on a matroidal error correction network.

关键词： network error correction code error pattern imagi-nary error channels extended network matroid

Efficient Schemes for Securing Network Coding Against Wiretapping

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2013年第4期18卷 355-362页

作者： liu guangjun ZHOU Hang State Key Laboratory of Integrated Service Networks Xidian University College of Science Engineering University of the Chinese People's Armed Police Force

Existing solutions for secure network coding either bring significant bandwidth overhead or incur a high computational complexity. For exploiting low-overhead mechanism for secure network coding against wiretapping, three efficient schemes are proposed for the applications with different security requirements. The basic idea behind this paper is first to encrypt a small part of source vectors and then subject the remaining original source vectors and the encrypted vectors to a special linear transformation. Also, a lightweight version of this scheme is then presented for resource-constrained networks. Moreover, an extensive scheme with enhanced security is also considered. All proposals are shown to have properties of lower security complexity and smaller bandwidth usage compared with the existing solutions. Also, the proposals can be easy to achieve flexible levels of security for various applications.

关键词： network coding security wiretapping pseudorandom function encryption

Connectivity of sparse vehicular ad hoc networks with channel randomness

在线全文

学校读者我要写书评

暂无评论

High Technology Letters 2010年第4期16卷 389-394页

作者：米振强 Yang Yang An Jianwei liu guangjun Department of Information Engineering University of Science and Technology Beijing Beijing 100083 P.R. China Department of Aerospace Engineering Ryerson University Toronto Canada M5A 2C9

In this paper,we investigate the connectivity of vehicular ad hoc networks in free-flow traffic situationwith channel *** order to illustrate the realistic environment,we consider that vehiclesare distributed in free-flow highway according to a Poisson point process,and signal propagation betweenconnected vehicles is subjected to log-normal shadowing *** obtain the distribution of the spaceheadway between successive vehicles and the distribution of signal coverage,which allows us to use theequivalent M/G/∞ queue theory to model the connectivity of VANETs in the form of average broadcastpercolation distance and average number of connected ***,extensive simulation studies are conductedto evaluate the obtained *** analytical model presented here is able to describe the impactof various system parameters,including traffic parameters and signal propagation parameters on the *** use our analytical results,along with the common signal propagation data,to understandimpact of channel randomness on the connectivity of VANETs.

关键词：网络连接随机性影响车辆渠道稀疏信号覆盖信号传播交通状况

Security Analysis on a Remote Data Auditing Scheme for Distributed Storage Systems

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2020年第6期25卷 527-530页

作者： liu guangjun ZHANG Lining LI Xiangjun School of Information Engineering Xi’an UniversityXi'an 710065ShaanxiChina

Remote data auditing becomes critical to ensure the storage reliability in distributed cloud ***,Le et al proposed an efficient private data auditing scheme NC-Audit designed for regenerating codes,which claimed that NC-Audit can effectively realize privacy-preserving data auditing for distributed storage ***,our analysis shows that NC-Audit is not secure for that the adversarial cloud can forge some illegal blocks to cheat the auditor successfully with a high probability even without storing the user’s whole data,when the coding field is large enough.

关键词： data auditing regeneration code network coding distributed storage cloud computing

2-Level R-tree Index Based on Spatial Grids and Hilbert R-tree

在线全文

学校读者我要写书评

暂无评论

Geo-Spatial Information Science 2006年第2期9卷 135-141页

作者： GUO Jing liu guangjun DONG Xurong GUO Lei Beijing Institute of Command and Technology of Equipment 1 Jingjia Road Huairou District Beijing 101416 China

Multi-level spatial index techniques are always used in large spatial databases. After a general survey of R-tree relevant techniques, this paper presents a novel 2-level index structure, which is based on the schemas of spatial grids, Hilbert R-tree and common R-tree. This structure is named H2R-tree, and it is specifically suitable for the indexing highly skewed, distributed, and large spatial database. Algorithms and a sample are given subsequently.

关键词：空间参数 GIS 地理信息系统空间栅格