检索结果-内蒙古大学图书馆

Secure gossip against intermittently malicious agents

SYSTEMS & CONTROL LETTERS 2023年 171卷

作者： Fioravanti, Camilla Oliva, Gabriele Hadjicostis, Christoforos Univ Campus Biomed Rome Dept Engn Via Alvaro Portillo 21 I-00128 Rome Italy Univ Cyprus Dept Elect & Comp Engn 75 Kallipoleos Ave POB 20537 CY-1678 Nicosia Cyprus

Security of distributed consensus algorithms is rapidly becoming a matter of paramount importance. Existing approaches address it by identifying corrupted nodes and deleting them from the network, but this results in the permanent loss of the contribution of these agents even if they return to their proper functionality. In this paper, we consider the case when legitimate nodes might exhibit malicious behavior that occurs intermittently and only for certain time instants. In particular, we provide a strategy to ensure that corrupted values never get incorporated in consensus computations, but without having to permanently exclude any nodes from the network and allowing them to participate to the consensus calculations once they have regained proper behavior. This approach allows the network to use all available information to achieve consensus and preserves the graph connectivity. Moreover, the proposed protocol relaxes several of the assumptions traditionally required by alternative state of the art methodologies. Our approach is based on reiterated exchange and comparison among each node and its one- and two-hop neighbors, and amounts to a variation of the standard gossip algorithm in which three nodes are involved at each round. After analyzing the convergence of the proposed algorithm, simulations are carried out to illustrate its effectiveness. (c) 2022 Elsevier B.V. All rights reserved.

关键词： Security Multi -agent systems gossip algorithms Distributed averaging

来源：评论

学校读者我要写书评

暂无评论

Social Learning in Multi Agent Multi Armed Bandits

引用

PROCEEDINGS OF THE ACM ON MEASUREMENT AND ANALYSIS OF COMPUTING SYSTEMS 2019年第3期3卷 1–35页

作者： Sankararaman, Abishek Ganesh, Ayalvadi Shakkottai, Sanjay Univ Texas Austin Austin TX 78712 USA Univ Bristol Bristol Avon England

Motivated by emerging need of learning algorithms for large scale networked and decentralized systems, we introduce a distributed version of the classical stochastic Multi-Arm Bandit (MAB) problem. Our setting consists of a large number of agents n that collaboratively and simultaneously solve the same instance of K armed MAB to minimize the average cumulative regret over all agents. The agents can communicate and collaborate among each other only through a pairwise asynchronous gossip based protocol that exchange a limited number of bits. In our model, agents at each point decide on (i) which arm to play, (ii) whether to, and if so (iii) what and whom to communicate with. Agents in our model are decentralized, namely their actions only depend on their observed history in the past. We develop a novel algorithm in which agents, whenever they choose, communicate only arm-ids and not samples, with another agent chosen uniformly and independently at random. The per-agent regret scaling achieved by our algorithm is O((inverted right perpendicular)K/n(inverted left perpendicular)+log(n)/Delta log (T) + log(3)(n)loglog(n)/Delta(2))). Furthermore, any agent in our algorithm communicates (arm-ids to an uniformly and independently chosen agent) only a total of Theta(log(T)) times over a time interval of T. We compare our results to two benchmarks - one where there is no communication among agents and one corresponding to complete interaction, where an agent has access to the entire system history of arms played and rewards obtained of all agents. We show both theoretically and empirically, that our algorithm experiences a significant reduction both in per-agent regret when compared to the case when agents do not collaborate and each agent is playing the standard MAB problem (where regret would scale linearly in K), and in communication complexity when compared to the full interaction setting which requires T communication attempts by an agent over T arm pulls. Our result thus

关键词： Decentralized Systems gossip algorithms

来源：评论

学校读者我要写书评

暂无评论

Fault Tolerance Properties of gossip-Based Distributed Orthogonal Iteration Methods

引用

Procedia Computer Science 2013年 18卷 189-198页

作者： Hana Straková Gerhard Niederbrucker Wilfried N. Gansterer University of Vienna Research Group Theory and Applications of Algorithms Austria

In this paper, we investigate and compare the fault tolerance properties and resilience of gossip-based distributed orthog- onal iteration algorithms for the in-network computation of the extreme eigenpairs of matrix. gossip-based algorithms have many attractive properties, especially for loosely coupled distributed and decentralized systems, like P2P networks or sensor networks. Due to their randomized communication schedule and the fact that communication happens only between nearest neighbors, they are highly flexible with respect to the topology of the underlying system. Moreover, such algorithms have a big potential for high resilience against various types of failures. Lately, several gossip-based distributed eigensolvers based on orthogonal iteration method have been introduced. However, the performance of these algorithms in the presence of failures has not been analyzed yet. We illustrate that convergence properties, the numerical accuracy achieved, as well as resilience properties of gossip-based distributed orthogonal iteration are basically determined by the choice of the distributed data aggregation algorithm (DDAA) which is required within the algorithm for performing distributed reduction operations (such as summation or averaging) across the system. In particular, we illustrate that when using the proper combination of DDAA and distributed orthogonal iteration method, high accuracy can be achieved and even silent message loss can be tolerated without any loss in numerical accuracy.

关键词： Fault tolerance Self-healing algorithm gossip algorithms Distributed algorithm Randomized communication schedule Orthogonal iteration

来源：评论

学校读者我要写书评

暂无评论

Context-aware gossip in Ad hoc Vehicular Networks

引用

Procedia Computer Science 2019年 160卷 157-164页

作者： Ahmad Bennakhi Abdulhusain Ben Nakhi Abdullah Marafi Kuwait Institution for Scientific Research Shuwaikh Educational Kuwait City 13109 Kuwait

The purpose of this paper is to quantify and highlight the effects of how contextually guided gossip in ad hoc dynamic vehicular networks during emergency situations perform. Two traffic scenarios are simulated, each one of the scenarios was simulated with the effect of contextual filtering and without any filtering (broadcast gossip). Our environment assumes the minimum specifications available, which is the presence of an on-board unit only in each car. We also analyze the effect of applying such filtering and if it is worth applying in such a critical environment that has human lives at stake. The simulation results show that our proposed concept could be applied safely without much affecting the time that the gossip takes to reach other vehicles. The amount of redundant and unneeded messages transmitted is reduced drastically with higher road traffic.

关键词： gossip algorithms Vehicular Ad Hoc Networks Wireless Sensor Networks Network Performance

来源：评论

学校读者我要写书评

暂无评论

A PI consensus controller with gossip communication for clock synchronization in wireless sensors networks *

引用

IFAC Proceedings Volumes 2009年第20期42卷 78-83页

作者： Saverio Bolognani Ruggero Carli Sandro Zampieri Department of Information Engineering University of Padova Italy CCDC University of California at Santa Barbara CA 93106 USA

In this paper a distributed clock synchronization algorithm is proposed. The algorithm requires gossip asynchronous communication between the nodes of the network, and because of its proportional-integral (PI) structure it is able to compensate both initial offsets and different clock speeds. Convergence of the algorithm is proved and analysed with respect to the controller parameter, while scalability issues are addressed by simulations.

关键词： consensus randomized algorithms gossip algorithms clock synchronization

来源：评论

学校读者我要写书评

暂无评论

Distributed QR Factorization Based on Randomized algorithms 1

引用

9th International Conference on Parallel Processing and Applied Mathematics (PPAM)

作者： Strakova, Hana Gansterer, Wilfried N. Zemen, Thomas Univ Vienna Res Grp Theory & Applicat Algorithms A-1010 Vienna Austria Forschungszentrum Telecommun Vienna Austria

ISBN: (数字)9783642314643

ISBN: (纸本)9783642314636;9783642314643

Most parallel algorithms for matrix computations assume a static network with reliable communication and thus use fixed communication schedules. However, in situations where computer systems may change dynamically, in particular, when they have unreliable components, algorithms with randomized communication schedule may be an interesting alternative. We investigate randomized algorithms based on gossiping for the distributed computation of the QR factorization. The analyses of numerical accuracy showed that known numerical properties of classical sequential and parallel QR decomposition algorithms are preserved. Moreover, we illustrate that the randomized approaches are well suited for distributed systems with arbitrary topology and potentially unreliable communication, where approaches with fixed communication schedules have major drawbacks. The communication overhead compared to the optimal parallel QR decomposition algorithm (CAQR) is analyzed. The randomized algorithms have a much higher potential for trading off numerical accuracy against performance because their accuracy is proportional to the amount of communication invested.

关键词： distributed vs. parallel QR factorization decentralized QR factorization evaluation of distributed algorithms gossip algorithms push -sum algorithm randomized communication schedule fault-tolerance

来源：评论

学校读者我要写书评

暂无评论

DETECT INSIDER ATTACKS USING CNN IN DECENTRALIZED OPTIMIZATION

DETECT INSIDER ATTACKS USING CNN IN DECENTRALIZED OPTIMIZATI...

引用

IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

作者： Li, Gangqiang Wu, Sissi Xiaoxiao Zhang, Shengli Li, Qiang Shenzhen Univ Coll Elect & Informat Engn Shenzhen Peoples R China Univ Elect Sci & Technol China Sch Info & Commun Engn Chengdu Peoples R China Peng Cheng Lab Shenzhen Peoples R China

ISBN: (纸本)9781509066315

This paper studies the security issue of a gossip-based distributed projected gradient (DPG) algorithm, when it is applied for solving a decentralized multi-agent optimization. It is known that the gossip-based DPG algorithm is vulnerable to insider attacks because each agent locally estimates its (sub)gradient without any supervision. This work leverages the convolutional neural network (CNN) to perform the detection and localization of the insider attackers. Compared to the previous work, CNN can learn appropriate decision functions from the original state information without preprocessing through artificially designed rules, thereby alleviating the dependence on complex pre-designed models. Simulation results demonstrate that the proposed CNN-based approach can effectively improve the performance of detecting and localizing malicious agents, as compared with the conventional pre-designed score-based model.

关键词： Distributed optimization gossip algorithms insider attack convolutional neural network (CNN)

来源：评论

学校读者我要写书评

暂无评论

MADN - Multipath Ad-hoc Data Network Prototype and Experiments

MADN - Multipath Ad-hoc Data Network Prototype and Experimen...

引用

9th International Wireless Communications and Mobile Computing Conference (IWCMC)

作者： Angius, Fabio Bhiday, Aditya Gerla, Mario Pau, Giovanni Univ Calif Los Angeles Dept Comp Sci Los Angeles CA 90024 USA

ISBN: (纸本)9781467324809

This paper presents the first prototype of Multipath Ad-hoc Data Network (MADN) a clean slate protocol for ad-hoc wireless content distribution. Inspired by the recent advances on Information Centric Networking (ICN), MADN is namely a pull-based protocol that emphasizes on seamless route redundancy and multi-path data delivery. It is complementary to the former IP protocol and therefore does not implement primitives for machine-to-machine communication. In consideration of targeting specifically the wireless medium, it uses rateless encoded data packets to counterbalance packet loss and to benefit from multi-source data distribution. A major difference between MADN and previous works is the use of the BlooGo algorithm in place of the conventional routing protocols - e.g. random walks, landmarks or coordinate spaces. The main advantages of using BlooGo is that it delivers the packets in considerably less hops while it maintains alternative routes open as backup of the shortest ones. This paper serves two aims, firstly it proposes a new protocol for multipath content distribution in ad-hoc environments, secondly it presents its architecture and how this interfaces with the final applications. Ultimately, the implementation is intentionally kept modular in order to facilitate deploying and evaluation of new solutions and new configurations - e.g. different caching algorithms or different types of Erasure Codes - without major refactoring of the codebase.

关键词： ICN Ad-hoc networks content centric networks BlooGo gossip algorithms Peer-to-Peer

来源：评论

学校读者我要写书评

暂无评论

A PROJECTION-FREE DECENTRALIZED ALGORITHM FOR NON-CONVEX OPTIMIZATION

A PROJECTION-FREE DECENTRALIZED ALGORITHM FOR NON-CONVEX OPT...

引用

IEEE Global Conference on Signal and Information Processing (GlobalSIP)

作者： Wai, Hoi-To Scaglione, Anna Lafond, Jean Moulines, Eric Arizona State Univ Sch ECEE Tempe AZ 85287 USA Ecole Polytech CMAP Palaiseau France CNRS LTCI Telecom ParisTech Inst Mines Telecom Paris France

ISBN: (纸本)9781509045457

This paper considers a decentralized projection free algorithm for non-convex optimization in high dimension. More specifically, we propose a Decentralized Frank-Wolfe (DeFW) algorithm which is suitable when high dimensional optimization constraints are difficult to handle by conventional projection/proximal-based gradient descent methods. We present conditions under which the DeFW algorithm converges to a stationary point and prove that the rate of convergence is as fast as O(1/root T), where T is the iteration number. This paper provides the first convergence guarantee for Frank-Wolfe methods applied to non-convex decentralized optimization. Utilizing our theoretical findings, we formulate a novel robust matrix completion problem and apply DeFW to give an efficient decentralized solution. Numerical experiments are performed on realistic and synthetic data to support our findings.

关键词： non-convex optimization Frank-Wolfe method decentralized algorithms gossip algorithms matrix completion

来源：评论

学校读者我要写书评

暂无评论

Convergence Rates for Cooperation in Heterogeneous Populations

Convergence Rates for Cooperation in Heterogeneous Populatio...

引用

46th Asilomar Conference on Signals, Systems and Computers

作者： Bean, Andrew Kairouz, Peter Singer, Andrew Univ Illinois Urbana IL 61801 USA

ISBN: (纸本)9781467350518

We consider the problem of cooperative distributed estimation within a network of heterogeneous agents. In particular, we study the situation where each agent observes an independent stream of Bernoulli random variables, and the goal is for each to determine its own Bernoulli parameter. The agents of this population can be categorized into a small number of subgroups, where within each group the agents all have identical Bernoulli parameters. For a distributed algorithm based on consensus strategies, we examine the rate at which the agent's estimates converge to the correct values. We show that the expected squared error decreases nearly as fast as centralized ML estimation in a homogeneous population. In a heterogeneous population, we derive an approximation to the expected squared error, as a function of the number of observations. Finally, we present simulation results that compare the predicted expected squared error to that observed in the simulations.

关键词： gossip algorithms consensus diffusion adaptation distributed estimation distributed signal processing

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：