Network Connectivity and Fault-Tolerance Measures in Two-Dimensional Deployment Fields

A secure scheme for wireless sensor network is presented through dividing sensing area into clusters and using the overlap key sharing (OKS) concept in this paper. The two-dimensional sensing square is divided into a number of small squares called cells, four of which consist of a cluster called logical group. The overlap key sharing protocol creates long bit clusters as the key cluster pools and distributes a sub-group to store every sensor as the key cluster. Analysis and comparison demonstrate this scheme enhances the WSN security, realizes the flexile secure grades for WSNs, and has good network connectivity.

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Practical two-dimensional correlation power analysis and its backward fault-tolerance

Science China Information Sciences ◽

10.1007/s11432-016-0398-y ◽

2017 ◽

Vol 60 (6) ◽

Author(s):

An Wang ◽

Wenjing Hu ◽

Weina Tian ◽

Guoshuang Zhang ◽

Liehuang Zhu

Keyword(s):

Fault Tolerance ◽

Power Analysis ◽

Two Dimensional ◽

Correlation Power Analysis

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Hypercube Network Fault Tolerance: A Probabilistic Approach

Journal of Interconnection Networks ◽

10.1142/s0219265905001290 ◽

2005 ◽

Vol 06 (01) ◽

pp. 17-34 ◽

Cited By ~ 13

Author(s):

JIANER CHEN ◽

IYAD A. KANJ ◽

GUOJUN WANG

Keyword(s):

Fault Tolerance ◽

Lower Bounds ◽

Network Connectivity ◽

Point Of View ◽

Theoretical Point ◽

Node Failure ◽

Hypercube Network ◽

Network Fault Tolerance ◽

Hypercube Networks ◽

Network Fault

Extensive experiments and experience have shown that the well-known hypercube networks are highly fault tolerant. What is frustrating is that it seems very difficult to properly formulate and formally prove this important fact, despite extensive research efforts in the past two decades. Most proposed fault tolerance models for hypercube networks are only able to characterize very rare extreme situations thus significantly underestimating the fault tolerance power of hypercube networks, while for more realistic fault tolerance models, the analysis becomes much more complicated. In this paper, we develop new techniques that enable us to analyze a more realistic fault tolerance model and derive lower bounds for the probability of hypercube network fault tolerance in terms of node failure probability. Our results are both theoretically significant and practically important. From the theoretical point of view, our method offers very general and powerful techniques for formally proving lower bounds on the probability of network connectivity, while from the practical point of view, our results provide formally proven and precisely given upper bounds on node failure probabilities for manufacturers to achieve a desired probability for network connectivity. Our techniques are also useful and powerful for analysis of the performance of routing algorithms, and applicable to the study of other hierarchical network structures and to other network communication problems.

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Adaptive fault tolerance in two-dimensional systems

1996 IEEE International Symposium on Circuits and Systems. Circuits and Systems Connecting the World. ISCAS 96 ◽

10.1109/iscas.1996.540388 ◽

2002 ◽

Author(s):

C.D. Schmitz ◽

W.K. Jenkins

Keyword(s):

Fault Tolerance ◽

Two Dimensional

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Αυτόνομα δίκτυα παγκόσμιας κλίμακας για τη διαχείριση και διάθεση πληροφορίας

10.12681/eadd/18617 ◽

2009 ◽

Author(s):

Αντώνιος Χαζάπης

Keyword(s):

Fault Tolerance ◽

Data Management ◽

Overlay Networks ◽

Network Connectivity ◽

Global Scale ◽

Distributed Applications ◽

Distributed Data ◽

Large Network ◽

Range Queries ◽

Peer To Peer Systems

Structured peer-to-peer systems, or else Distributed Hash Tables (DHTs), are widely established as one of the most efficient platforms for global-scale, distributed data management. The resulting overlay networks tire based on the concept of equality and homogeneity of capabilities and obligations among participating parties. Their prominent features include scalability to extremely large network sizes and fault-tolerance. DHTs self-regulate and self-manage problems that may arise both at the layer of the physical infrastructure (unadvertised network connectivity failures, or unresponsiveness of computing systems hosting the overlay nodes), or the communication protocol (deliberate malicious behavior). The research presented in this dissertation, focuses on the fact that proposed DHT algorithms and implementations, succeed on delivering only a subset of data management operations, such as insertion and lookup based on an identification key. They do not allow altering information already stored and tied to a specific identifier, or searching and retrieving a range of keys (range queries). Although these functions represent important research targets in the field of databases (distributed or not) and many implementation options have been suggested in related literature, the applicability of corresponding algorithms in DHTs is limited by tire particular, peculiar characteristics of the P2P environment. A DHT is highly dynamic in nature, thus no specific node can be trusted to solitary handle information crucial to the completion of the distributed operation. Moreover, all operations should account for the special techniques employed by DHTs to distribute available data to participating peers. For example, the difficulty in supporting mutable data lies in the fact that each individual stored key-value pair is automatically copied to a dynamic set of nodes. For most widespread protocols, information, once stored in a DHT, cannot be changed. Accordingly, most DHT based range query implementations, are designed so that the search function runs on a separate layer of software, on top of the overlay, disregarding the existence of data replicas and without exploiting the network configuration, which already encodes peer and data relationships in its structure. We propose and evaluate the implementations of two alternatives for updating key-value pairs in DHTs: A lookup algorithm that helps in maintaining a loose consistency between multiple versions of data replicas, as well as a new DHT protocol - XOROS, based on the Kademlia routing scheme, which inherently supports serializable and consistent data changes. XOROS is also tolerant to “Byzantine” behavior - intentional non-compliance with its protocol by some participants. In addition, we present a protocol that addresses the problem of implementing complex, single or multi-dimensional range queries in DHTs. In all cases, the extra functionality is offered without sacrificing fundamental properties of the system, such as scalability and fault tolerance. Therefore, the resulting infrastructure for storing, retrieving and searching data can form the basis for supporting a multitude of novel, global-scale distributed applications. The proposed algorithms and protocols have been thoroughly evaluated, using a prototype integrated environment for implementing and evaluating P2P networks. Experimental results are used to assess how the various overlay parameters affect its performance and help in proposing directions for future work.

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Two New Three-Dimensional Networks Constructed on Polyoxovanadates

Australian Journal of Chemistry ◽

10.1071/ch07182 ◽

2007 ◽

Vol 60 (11) ◽

pp. 871 ◽

Cited By ~ 9

Author(s):

Yan-fei Qi ◽

Dongrong Xiao ◽

Enbo Wang ◽

Zhiming Zhang ◽

Xinlong Wang

Keyword(s):

Thermogravimetric Analysis ◽

Rare Case ◽

Three Dimensional ◽

Network Connectivity ◽

Two Dimensional ◽

Crystal Data ◽

X Ray Diffraction ◽

Inorganic Hybrid ◽

X Ray

To investigate the role of polyoxovanadates in network connectivity, two new organic–inorganic hybrid vanadates with three-dimensional entangled coordination frameworks, namely [Cu2(biim)3V4O12] 1 and [Co2(biim)3V4O12]·4H2O 2 have been synthesized and characterized by infrared (IR), thermogravimetric analysis (TGA), and single-crystal X-ray diffraction. Crystal data for compound 1: triclinic, P-1, a 9.504(2), b 10.650(2), c 11.993(2) Å; α 72.13(3), β 76.02(3), γ 65.40(3)°; V 1041.4(4) Å3, Z 2, R(final) 0.0492. Crystal data for compound 2: triclinic, P-1, a 9.037(3), b 10.577(2), c 11.9470(2) Å; α 87.80(3), β 81.71(3), γ 85.29(3)°; V 1125.8(4) Å3, Z 1, R(final) 0.0774. Compound 1 is a three-dimensional inclined hetero-catenated framework designed from two two-dimensional sub-layers, [Cu(biim)V4O12] and [Cu(biim)2]. Compound 2 is a rare case of a self-catenated ‘ilc’ network that displays an unusual 424·5·63 topology with the binuclear {Co2O4N6} units as eight-connected nodes.

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Spectrophotometric measurements of objective-prism spectra

Symposium - International Astronomical Union ◽

10.1017/s007418090005333x ◽

1966 ◽

Vol 24 ◽

pp. 118-119

Author(s):

Th. Schmidt-Kaler

Keyword(s):

Progress Report ◽

Two Dimensional ◽

Objective Prism ◽

Made In

I should like to give you a very condensed progress report on some spectrophotometric measurements of objective-prism spectra made in collaboration with H. Leicher at Bonn. The procedure used is almost completely automatic. The measurements are made with the help of a semi-automatic fully digitized registering microphotometer constructed by Hög-Hamburg. The reductions are carried out with the aid of a number of interconnected programmes written for the computer IBM 7090, beginning with the output of the photometer in the form of punched cards and ending with the printing-out of the final two-dimensional classifications.

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