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LSB and DCT steganographic detection using compressive sensing

Journal of Information Hiding and Multimedia Signal Processing 2014年第1期5卷 20-32页

作者： Patsakis, Constantinos Aroukatos, Nikolaos G. Distributed Systems Group School of Computer Science and Statistics Trinity College College Green Dublin 2 Ireland Department of Informatics University of Piraeus 80 Karaoli and Dimitriou str 18534 Piraeus Greece

During the last years, a large number of information in digital form has been exchanged all over the world. Several techniques have been developed in order to protect the users' privacy of digital content. Steganography is one of them. Its use dates back for many centuries, yet it has been used profoundly in the last decades, as the proper mathematical background has been developed along with the need of the music and film industries. One aspect of this development is the use of DRM (Digital Right Management) as the main method of protecting digital assets. This work presents two new detection methods of steganographic content through the use of compressive sensing. The first method is a probabilistic filter that can increase the probability of detecting steganographic content in images, in case where the LSB method is used. The second one helps identifying the original from stego images when DCT steganography is used, after applying a filter with compressive sensing technique. © 2014.

关键词： Steganography

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Uncertainty aware hybrid clock synchronisation in Wireless Sensor Networks 8

Uncertainty aware hybrid clock synchronisation in Wireless S...

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8th International Conference on Mobile Ubiquitous Computing, systems, Services and Technologies, UBICOMM 2014

作者： Steup, Christoph Zug, Sebastian Kaiser, Jörg Breuhan, Andy Department of Distributed Systems Faculty of Computer Science Otto-von-Guericke-University Magdeburg Germany Rohde and Schwarz DVS GmbH Germany

Wireless Sensor Networks, aiming to monitor the real world's phenomena reliably, need to combine and postprocess the detected individual events. This is not possible without reliable information of the context of the individual event. One such information of very high importance is time. It enables ordering of events as well as deduction of further data like rates and durations. An unreliable time base influences not only the ordering of events, but also the deduced values, which in consequence are unreliable as well. Therefore the synchronization of the clocks of the individual nodes is of high importance to the reliability of the system. On the other hand tight and reliable synchronization typically induces a large message overhead, which is often not tolerable in WSN scenarios. This paper proposes a new hybrid synchronization mechanism enabling tight synchronization in single hop environments and looser synchronization in multi hop environments. The lack of a guaranteed synchronization precision is mitigated by an explicit synchronization uncertainty, which is passed to the application. This enables the application to react to changes in the current synchronization precision.

关键词： Wireless sensor networks

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Using restricted transactional memory to build a scalable in-memory database 14

Using restricted transactional memory to build a scalable in...

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9th ACM European Conference on computer systems, EuroSys 2014

作者： Wang, Zhaoguo Qian, Hao Li, Jinyang Chen, Haibo School of Computer Science Fudan University China Institute of Parallel and Distributed Systems Shanghai Jiao Tong University China Department of Computer Science New York University United States

ISBN: (纸本)9781450327046

The recent availability of Intel Haswell processors marks the transition of hardware transactional memory from research toys to mainstream reality. DBX is an in-memory database that uses Intel's restricted transactional memory (RTM) to achieve high performance and good scalability across multicore machines. The main limitation (and also key to practicality) of RTM is its constrained working set size: An RTM region that reads or writes too much data will always be aborted. The design of DBX addresses this challenge in several ways. First, DBX builds a database transaction layer on top of an underlying shared-memory store. The two layers use separate RTM regions to synchronize shared memory access. Second, DBX uses optimistic concurrency control to separate transaction execution from its commit. Only the commit stage uses RTM for synchronization. As a result, the working set of the RTMs used scales with the meta-data of reads and writes in a database transaction as opposed to the amount of data read/written. Our evaluation using TPC-C workload mix shows that DBX achieves 506,817 transactions per second on a 4-core machine. Copyright © 2007 by the Association for Computing Machinery, Inc.

关键词： Concurrency control

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Computation and communication efficient graph processing with distributed immutable view 14

Computation and communication efficient graph processing wit...

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23rd ACM Symposium on High-Performance Parallel and distributed Computing, HPDC 2014

作者： Chen, Rong Ding, Xin Wang, Peng Chen, Haibo Zang, Binyu Guan, Haibing Shanghai Key Laboratory of Scalable Computing and Systems Institute of Parallel and Distributed Systems Shanghai Jiao Tong University China Shanghai Key Laboratory of Scalable Computing and Systems Department of Computer Science Shanghai Jiao Tong University China

ISBN: (纸本)9781450327480

Cyclops is a new vertex-oriented graph-parallel framework for writing distributed graph analytics. Unlike existing distributed graph computation models, Cyclops retains simplicity and computation-efficiency by synchronously computing over a distributed immutable view, which grants a vertex with read-only access to all its neighboring vertices. The view is provided via readonly replication of vertices for edges spanning machines during a graph cut. Cyclops follows a centralized computation model by assigning a master vertex to update and propagate the value to its replicas unidirectionally in each iteration, which can significantly reduce messages and avoid contention on replicas. Being aware of the pervasively available multicore-based clusters, Cyclops is further extended with a hierarchical processing model, which aggregates messages and replicas in a single multicore machine and transparently decomposes each worker into multiple threads ondemand for different stages of computation. We have implemented Cyclops based on an open-source Pregel clone called Hama. Our evaluation using a set of graph algorithms on an in-house multicore cluster shows that Cyclops outperforms Hama from 2.06X to 8.69X and 5.95X to 23.04X using hash-based and Metis partition algorithms accordingly, due to the elimination of contention on messages and hierarchical optimization for the multicore-based clusters. Cyclops (written in Java) also has comparable performance with PowerGraph (written in C++) despite the language difference, due to the significantly lower number of messages and avoided contention. Copyright © 2014 ACM.

关键词： Iterative methods

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Correntropy Supervised Non-negative Matrix Factorization

Correntropy Supervised Non-negative Matrix Factorization

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International Joint Conference on Neural Networks

作者： Wenju Zhang Naiyang Guan Dacheng Tao Bin Mao Xuhui Huang Zhigang Luo Science and Technology on Parallel and Distributed Processing Laboratory College of Computer National University of Defense Technology Changsha Hunan China 410073 Center for Quantum Computation and Intelligent Systems FEIT University of Technology Sydney Sydney NSW 2007 Australia College of Science National University of Defense Technology Changsha Hunan China 410073 Department of Computer Science and Technology College of Computer National University of Defense Technology Changsha Hunan China 410073

ISBN: (纸本)9781479919611

Non-negative matrix factorization (NMF) is a powerful dimension reduction method and has been widely used in many pattern recognition and computer vision problems. However, conventional NMF methods are neither robust enough as their loss functions are sensitive to outliers, nor discriminative because they completely ignore labels in a dataset. In this paper, we proposed a correntropy supervised NMF (CSNMF) to simultaneously overcome aforementioned deficiencies. In particular, CSNMF maximizes the correntropy between the data matrix and its reconstruction in low-dimensional space to inhibit outliers during learning the subspace, and narrows the minimizes the distances between coefficients of any two samples with the same class labels to enhance the subsequent classification performance. To solve CSNMF, we developed a multiplicative update rules and theoretically proved its convergence. Experimental results on popular face image datasets verify the effectiveness of CSNMF comparing with NMF, its supervised variants, and its robustified variants.

关键词： NMF subsequent classification NMF protocol matrix decomposition outliers Nonnegative LOSS FUNCTION images REDUCTION METHODS Dataset computer vision

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HSkip+: A self-stabilizing overlay network for nodes with heterogeneous bandwidths 14

HSkip+: A self-stabilizing overlay network for nodes with he...

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14th IEEE International Conference on Peer-to-Peer Computing, IEEE P2P 2014

作者： Feldotto, Matthias Scheideler, Christian Graffi, Kalman Heinz Nixdorf Institute Department of Computer Science University of Paderborn Germany Theory of Distributed Systems Group Department of Computer Science University of Paderborn Germany Technology of Social Networks Group Department of Computer Science University of Düsseldorf Germany

ISBN: (纸本)9781479962013

In this paper we present and analyze HSkip+, a self-stabilizing overlay network for nodes with arbitrary heterogeneous bandwidths. HSkip+ has the same topology as the Skip+ graph proposed by Jacob et al. [1] but its self-stabilization mechanism significantly outperforms the self-stabilization mechanism proposed for Skip+. Also, the nodes are now ordered according to their bandwidths and not according to their identifiers. Various other solutions have already been proposed for overlay networks with heterogeneous bandwidths, but they are not self-stabilizing. In addition to HSkip+ being self-stabilizing, its performance is on par with the best previous bounds on the time and work for joining or leaving a network of peers of logarithmic diameter and degree and arbitrary bandwidths. Also, the dilation and congestion for routing messages is on par with the best previous bounds for such networks, so that HSkip+ combines the advantages of both worlds. Our theoretical investigations are backed by simulations demonstrating that HSkip+ is indeed performing much better than Skip+ and working correctly under high churn rates. © 2014 IEEE.

关键词： Bandwidth

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Bipartite-oriented distributed graph partitioning for big learning 14

Bipartite-oriented distributed graph partitioning for big le...

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5th ACM Asia-Pacific Workshop on systems, APSYS 2014

作者： Chen, Rong Shi, Jiaxin Zang, Binyu Guan, Haibing Shanghai Key Laboratory of Scalable Computing and Systems Institute of Parallel and Distributed Systems Shanghai Jiao Tong University China Shanghai Key Laboratory of Scalable Computing and Systems Department of Computer Science Shanghai Jiao Tong University China

ISBN: (纸本)9781450330244

Many machine learning and data mining (MLDM) problems like recommendation, topic modeling and medical diagnosis can be modeled as computing on bipartite graphs. However, most distributed graph-parallel systems are oblivious to the unique characteristics in such graphs and existing online graph partitioning algorithms usually causes excessive replication of vertices as well as significant pressure on network communication. This article identifies the challenges and opportunities of partitioning bipartite graphs for distributed MLDM processing and proposes BiGraph, a set of bipartite-oriented graph partitioning algorithms. BiGraph leverages observations such as the skewed distribution of vertices, discriminated computation load and imbalanced data sizes between the two subsets of vertices to derive a set of optimal graph partition algorithms that result in minimal vertex replication and network communication. BiGraph has been implemented on PowerGraph and is shown to have a performance boost up to 17.75X (from 1.38X) for four typical MLDM algorithms, due to reducing up to 62% vertex replication, and up to 96% network traffic. © 2014 ACM.

关键词： Data mining

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Concurrent and consistent virtual machine introspection with hardware transactional memory

Concurrent and consistent virtual machine introspection with...

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20th IEEE International Symposium on High Performance computer Architecture, HPCA 2014

作者： Liu, Yutao Xia, Yubin Guan, Haibing Zang, Binyu Chen, Haibo Shanghai Key Laboratory of Scalable Computing and Systems Institute of Parallel and Distributed Systems Shanghai Jiao Tong University China Shanghai Key Laboratory of Scalable Computing and Systems Department of Computer Science Shanghai Jiao Tong University China

ISBN: (纸本)9781479930975

Virtual machine introspection, which provides tamperresistant, high-fidelity 'out of the box' monitoring of virtual machines, has many prominent security applications including VM-based intrusion detection, malware analysis and memory forensic analysis. However, prior approaches are either intrusive in stopping the world to avoid race conditions between introspection tools and the guest VM, or providing no guarantee of getting a consistent state of the guest VM. Further, there is currently no effective means for timely examining the VM states in question. In this paper, we propose a novel approach, called TxIntro, which retrofits hardware transactional memory (HTM) for concurrent, timely and consistent introspection of guest VMs. Specifically, TxIntro leverages the strong atomicity of HTM to actively monitor updates to critical kernel data structures. Then TxIntro can mount introspection to timely detect malicious tampering. To avoid fetching inconsistent kernel states for introspection, TxIntro uses HTM to add related synchronization states into the read set of the monitoring core and thus can easily detect potential inflight concurrent kernel updates. We have implemented and evaluated TxIntro based on Xen VMM on a commodity Intel Haswell machine that provides restricted transactional memory (RTM) support. To demonstrate the effectiveness of TxIntro, we implemented a set of kernel rootkit detectors using TxIntro. Evaluation results show that TxIntro is effective in detecting these rootkits, and is efficient in adding negligible performance overhead. © 2014 IEEE.

关键词： Malware

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Semantic self-management and mediation for home service platforms 44

Semantic self-management and mediation for home service plat...

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44. Jahrestagung der Gesellschaft fur Informatik INFORMATIK 2014 - Big Data - Komplexitat meistern - Big Data - Mastering Complexity: 44th Annual Meeting of the Society for computer science, INFORMATICS 2014

作者： Schaefer, Jan RheinMain University of Applied Sciences Design Computer Science Media Department Distributed Systems Lab. Unter den Eichen 5 WiesbadenD-65195 Germany

ISBN: (纸本)9783885796268

Service-oriented computing has long outgrown the enterprise. Today, personal livingenvironments feature an increasing number of convenience-, health-and securityrelatedapplications provided by distributed interacting devices and services (oftencalled smart homes), which do not only support users but require management taskssuch as application installation, configuration and continuous maintenance. Thesetasks are becoming complex and error-prone. One way to escape this situation is toenable service platforms to configure and manage themselves. The approach presentedhere extends services with semantic descriptions to enable platform-independent autonomousservice level management and mediation using model driven architectureand autonomic computing concepts. It has been implemented as a semantic autonomicmanager, whose concept, prototypical implementation and evaluation are presented.

关键词： Smart homes

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A Practitioner's Guide to Software-Based Soft-Error Mitigation Using AN-Codes

A Practitioner's Guide to Software-Based Soft-Error Mitigati...

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IEEE International Symposim on High Assurance systems Engineering

作者： Martin Hoffmann Peter Ulbrich Christian Dietrich Horst Schirmeier Daniel Lohmann Wolfgang Schröder-Preikschat Chair of Distributed Systems and Operating Systems Friedrich-Alexander University Erlangen-Nuremberg Germany Department of Computer Science 12 Technische Universität Dortmund Germany

Arithmetic error coding schemes (AN codes) are a well known and effective technique for soft error mitigation. Although coding theory being a rich area of mathematics, their implementation seems to be fairly easy. However, compliance with the theory can be lost easily while moving towards an actual implementation - finally jeopardizing the aspired fault-tolerance characteristics. In this paper, we present our experiences and lessons learned from implementing AN codes in the Cored dependable voter. We focus on the challenges and pitfalls in the transition from maths to machine code for a binary computer from a systems perspective. Our results show, that practical misconceptions (such as the use of prime numbers) and architecture-dependent implementation glitches occur on every stage of this transition. We identify typical pitfalls and describe practical measures to find and resolve them. Our measures eliminate all remaining SDCs in the Cored voter, which is validated by an extensive fault-injection campaign that covers 100 percent of the fault space for 1-bit and 2-bit errors.

关键词： Encoding Error probability Registers Hardware Fault tolerance

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