A New Scheme for Removing Duplicate Files from Smart Mobile Devices

The continuous development of the information technology and mobile communication world and the potentials available in the smart devices make these devices widely used in daily life. The mobile applications with the internet are distinguished simple, essay to use in any time/anywhere, communication between relatives and friends in different places in the world. The social application networks make these devices received several of the duplicate files daily which lead to many drawbacks such inefficient use of storage, low performance of CPU, RAM, and increasing consumption battery. In this paper, we present a good scheme to remove from the duplicate files, and we focus on image files as a common case in social apps. Our work overcomes on the above-mentioned issues and focuses to use hash function and Huffman code to build unique code for each image. Our experiments improve the performance from 1046770, 1995808 ns to 950000, and 1981154 ns in Galaxy and HUAWEI, respectively. In the storage side, the proposed scheme saves storage space from 1.9 GB, 1.24 GB to 2 GB, and 1.54 GB, respectively

DeltaFS: Pursuing Zero Update Overhead via Metadata-Enabled Delta Compression for Log-structured File System on Mobile Devices

Data compression has been widely adopted to release mobile devices from intensive write pressure. Delta compression is particularly promising for its high compression efficacy over conventional compression methods. However, this method suffers from non-trivial system overheads incurred by delta maintenance and read penalty, which prevents its applicability on mobile devices. To this end, this paper proposes DeltaFS, a metadata-enabled Delta compression on log-structured File System for mobile devices, to achieve utmost compressing efficiency and zero hardware costs. DeltaFS smartly exploits the out-of-place updating ability of Log-structured File System (LFS) to alleviate the problems of write amplification, which is the key bottleneck for delta compression implementation. Specifically, DeltaFS utilizes the inline area in file inodes for delta maintenance with zero hardware cost, and integrates an inline area manage strategy to improve the utilization of constrained inline area. Moreover, a complimentary delta maintenance strategy is incorporated, which selectively maintains delta chunks in the main data area to break through the limitation of constrained inline area. Experimental results show that DeltaFS substantially reduces write traffics by up to 64.8\%, and improves the I/O performance by up to 37.3\%

CYBER SECURITY IN INDUSTRIAL CONTROL SYSTEMS (ICS): A SURVEY OF ROWHAMMER VULNERABILITY

Increasing dependence on Information and Communication Technologies (ICT) and especially on the Internet in Industrial Control Systems (ICS) has made these systems the primary target of cyber-attacks. As ICS are extensively used in Critical Infrastructures (CI), this makes CI more vulnerable to cyber-attacks and their protection becomes an important issue. On the other hand, cyberattacks can exploit not only software but also physics; that is, they can target the fundamental physical aspects of computation. The newly discovered RowHammer (RH) fault injection attack is a serious vulnerability targeting hardware on reliability and security of DRAM (Dynamic Random Access Memory). Studies on this vulnerability issue raise serious security concerns.  The purpose of this study was to overview the RH phenomenon in DRAMs and its possible security risks on ICSs and to discuss a few possible realistic RH attack scenarios for ICSs. The results of the study revealed that RH is a serious security threat to any computer-based system having DRAMs, and this also applies to ICS

Service Abstractions for Scalable Deep Learning Inference at the Edge

Deep learning driven intelligent edge has already become a reality, where millions of mobile, wearable, and IoT devices analyze real-time data and transform those into actionable insights on-device. Typical approaches for optimizing deep learning inference mostly focus on accelerating the execution of individual inference tasks, without considering the contextual correlation unique to edge environments and the statistical nature of learning-based computation. Specifically, they treat inference workloads as individual black boxes and apply canonical system optimization techniques, developed over the last few decades, to handle them as yet another type of computation-intensive applications. As a result, deep learning inference on edge devices still face the ever increasing challenges of customization to edge device heterogeneity, fuzzy computation redundancy between inference tasks, and end-to-end deployment at scale. In this thesis, we propose the first framework that automates and scales the end-to-end process of deploying efficient deep learning inference from the cloud to heterogeneous edge devices. The framework consists of a series of service abstractions that handle DNN model tailoring, model indexing and query, and computation reuse for runtime inference respectively. Together, these services bridge the gap between deep learning training and inference, eliminate computation redundancy during inference execution, and further lower the barrier for deep learning algorithm and system co-optimization. To build efficient and scalable services, we take a unique algorithmic approach of harnessing the semantic correlation between the learning-based computation. Rather than viewing individual tasks as isolated black boxes, we optimize them collectively in a white box approach, proposing primitives to formulate the semantics of the deep learning workloads, algorithms to assess their hidden correlation (in terms of the input data, the neural network models, and the deployment trials) and merge common processing steps to minimize redundancy

Towards Data Optimization in Storages and Networks

Title from PDF of title page, viewed on August 7, 2015Dissertation advisors: Sejun Song and Baek-Young ChoiVitaIncludes bibliographic references (pages 132-140)Thesis (Ph.D.)--School of Computing and Engineering. University of Missouri--Kansas City, 2015We are encountering an explosion of data volume, as a study estimates that data will amount to 40 zeta bytes by the end of 2020. This data explosion poses significant burden not only on data storage space but also access latency, manageability, and processing and network bandwidth. However, large portions of the huge data volume contain massive redundancies that are created by users, applications, systems, and communication models. Deduplication is a technique to reduce data volume by removing redundancies. Reliability will be even improved when data is replicated after deduplication. Many deduplication studies such as storage data deduplication and network redundancy elimination have been proposed to reduce storage consumption and network bandwidth consumption. However, existing solutions are not efficient enough to optimize data delivery path from clients to servers through network. Hence we propose a holistic deduplication framework to optimize data in their path. Our deduplication framework consists of three components including data sources or clients, networks, and servers. The client component removes local redundancies in clients, the network component removes redundant transfers coming from different clients, and the server component removes redundancies coming from different networks. We designed and developed components for the proposed deduplication framework. For the server component, we developed the Hybrid Email Deduplication System that achieves a trade-off of space savings and overhead for email systems. For the client component, we developed the Structure Aware File and Email Deduplication for Cloudbased Storage Systems that is very fast as well as having good space savings by using structure-based granularity. For the network component, we developed a system called Software-defined Deduplication as a Network and Storage service that is in-network deduplication, and that chains storage data deduplication and network redundancy elimination functions by using Software Defined Network to achieve both storage space and network bandwidth savings with low processing time and memory size. We also discuss mobile deduplication for image and video files in mobile devices. Through system implementations and experiments, we show that the proposed framework effectively and efficiently optimizes data volume in a holistic manner encompassing the entire data path of clients, networks and storage servers.Introduction -- Deduplication technology -- Existing deduplication approaches -- HEDS: Hybrid Email Deduplication System -- SAFE: Structure-aware File and Email Deduplication for cloud-based storage systems -- SoftDance: Software-defined Deduplication as a Network and Storage Service -- Moblie de-duplication -- Conclusion

Weight Based Deduplication for Minimizing Data Replication in Public Cloud Storage

260-269The approach to optimize the data replication in public cloud storage when targeting the multiple instances is one of the challenging issues to process the text data. The amount of digital data has been increasing exponentially. There is a need to reduce the amount of storage space by storing the data efficiently. In cloud storage environment, the data replication provides high availability with fault tolerance system. An effective approach of deduplication system using weight based method is proposed at the target level in order to reduce the unwanted storage spaces in cloud. Storage space can be efficiently utilized by removing the unpopular files from the secondary servers. Target level consumes less processing power than source level deduplication. Multiple input text documents are stored into dropbox cloud. The top text features are detected using the Term Frequency (TF) and Named Entity Recognition (NER) and they are stored in text database. After storing the top features in database, fresh text documents are collected to find the popular and unpopular files in order to optimize the existing text corpus of cloud storage. Top Text features of the freshly collected text documents are detected using TF and NER and these unique features after the removing the duplicate features cleaning are compared with the existing features stored in the database. On the comparison, relevant text documents are listed. After listing the text documents, document frequency, document weight and threshold factor are detected. Depending on average threshold value, the popular and unpopular files are detected. The popular files are retained in all the storage nodes to achieve the full availability of data and unpopular files are removed from all the secondary servers except primary server. Before deduplication, the storage space occupied in the dropbox cloud is 8.09 MB. After deduplication, the unpopular files are removed from secondary storage nodes and the storage space in the dropbox cloud is optimized to 4.82MB. Finally, data replications are minimized and 45.60% of the cloud storage space is efficiently saved by applying the weight based deduplication system

CoAP Infrastructure for IoT

The Internet of Things (IoT) can be seen as a large-scale network of billions of smart devices. Often IoT devices exchange data in small but numerous messages, which requires IoT services to be more scalable and reliable than ever. Traditional protocols that are known in the Web world does not fit well in the constrained environment that these devices operate in. Therefore many lightweight protocols specialized for the IoT have been studied, among which the Constrained Application Protocol (CoAP) stands out for its well-known REST paradigm and easy integration with existing Web. On the other hand, new paradigms such as Fog Computing emerges, attempting to avoid the centralized bottleneck in IoT services by moving computations to the edge of the network. Since a node of the Fog essentially belongs to relatively constrained environment, CoAP fits in well. Among the many attempts of building scalable and reliable systems, Erlang as a typical concurrency-oriented programming (COP) language has been battle tested in the telecom industry, which has similar requirements as the IoT. In order to explore the possibility of applying Erlang and COP in general to the IoT, this thesis presents an Erlang based CoAP server/client prototype ecoap with a flexible concurrency model that can scale up to an unconstrained environment like the Cloud and scale down to a constrained environment like an embedded platform. The flexibility of the presented server renders the same architecture applicable from Fog to Cloud. To evaluate its performance, the proposed server is compared with the mainstream CoAP implementation on an Amazon Web Service (AWS) Cloud instance and a Raspberry Pi 3, representing the unconstrained and constrained environment respectively. The ecoap server achieves comparable throughput, lower latency, and in general scales better than the other implementation in the Cloud and on the Raspberry Pi. The thesis yields positive results and demonstrates the value of the philosophy of Erlang in the IoT space

A Survey of Performance Optimization for Mobile Applications

Nowadays there is a mobile application for almost everything a user may think of, ranging from paying bills and gathering information to playing games and watching movies. In order to ensure user satisfaction and success of applications, it is important to provide high performant applications. This is particularly important for resource constraint systems such as mobile devices. Thereby, non-functional performance characteristics, such as energy and memory consumption, play an important role for user satisfaction. This paper provides a comprehensive survey of non-functional performance optimization for Android applications. We collected 155 unique publications, published between 2008 and 2020, that focus on the optimization of non-functional performance of mobile applications. We target our search at four performance characteristics, in particular: responsiveness, launch time, memory and energy consumption. For each performance characteristic, we categorize optimization approaches based on the method used in the corresponding publications. Furthermore, we identify research gaps in the literature for future work