arXiv subjects

M-Tahar Kechadi

Publications and source records attributed to M-Tahar Kechadi.

At least 37 records · Page 2Linked to original sources

arXiv2017

A Tree-based Approach for Detecting Redundant Business Rules in very Large Financial Datasets

Net Asset Value (NAV) calculation and validation is the principle task of a fund administrator. If the NAV of a fund is calculated incorrectly then there is huge impact on the fund administrator; such as monetary compensation, reputational loss, or loss of business. In general, these companies use the same methodology to calculate the NAV of a fund, however the type of fund in question dictates the set of business rules used to validate this. Today, most Fund Administrators depend heavily on human resources due to the lack of an automated standardized solutions, however due to economic climate and the need for efficiency and costs reduction many banks are now looking for an automated solution with minimal human interaction; i.e., straight through processing (STP). Within the scope of a collaboration project that focuses on building an optimal solution for NAV validation, in this paper, we will present a new approach for detecting correlated business rules. We also show how we evaluate this approach using real-world financial data.

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arXiv2017

On a Distributed Approach for Density-based Clustering

Efficient extraction of useful knowledge from these data is still a challenge, mainly when the data is distributed, heterogeneous and of different quality depending on its corresponding local infrastructure. To reduce the overhead cost, most of the existing distributed clustering approaches generate global models by aggregating local results obtained on each individual node. The complexity and quality of solutions depend highly on the quality of the aggregation. In this respect, we proposed for distributed density-based clustering that both reduces the communication overheads due to the data exchange and improves the quality of the global models by considering the shapes of local clusters. From preliminary results we show that this algorithm is very promising.

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arXiv2017

Forensic Analysis of TomTom Navigation Application

In the forensic field of digital technology, there has been a great deal of investigation into the decoding of navigation systems of the brand TomTom. As TomTom is the market leader in navigation systems, a large number of these devices are investigated. These devices can hold an abundance of significant location information. Currently, it is possible with the use of multiple methods to make physical copies of mobile devices running Android. The next great forensic problem is all the various programs that can be installed on these devices. There is now an application available from the company TomTom in the Google Play Store. This application mimics a navigation system on your Android mobile device. Indeed, the TomTom application on Android can hold a great deal of information. In this paper, we present a process of forensic acquisition and analysis of the TomTom Android application. We focus on the following questions: Is there a possibility to find previously driven routes or GPS coordinates with timestamps in the memory of the mobile device? To investigate what is stored in these files, driving tests were performed. During these driving tests a copy was made of the most important file using a self-written program. The significant files were found and the data in these files was decoded. We show and analyse our results with Samsung mobile devices. We compare also these results with forensic acquisition from TomTom GPS devices.

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arXiv2017

Feature Selection Parallel Technique for Remotely Sensed Imagery Classification

Remote sensing research focusing on feature selection has long attracted the attention of the remote sensing community because feature selection is a prerequisite for image processing and various applications. Different feature selection methods have been proposed to improve the classification accuracy. They vary from basic search techniques to clonal selections, and various optimal criteria have been investigated. Recently, methods using dependence-based measures have attracted much attention due to their ability to deal with very high dimensional datasets. However, these methods are based on Cramers V test, which has performance issues with large datasets. In this paper, we propose a parallel approach to improve their performance. We evaluate our approach on hyper-spectral and high spatial resolution images and compare it to the proposed methods with a centralized version as preliminary results. The results are very promising.

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arXiv2017

Toward a Distributed Knowledge Discovery system for Grid systems

During the last decade or so, we have had a deluge of data from not only science fields but also industry and commerce fields. Although the amount of data available to us is constantly increasing, our ability to process it becomes more and more difficult. Efficient discovery of useful knowledge from these datasets is therefore becoming a challenge and a massive economic need. This led to the need of developing large-scale data mining (DM) techniques to deal with these huge datasets either from science or economic applications. In this chapter, we present a new DDM system combining dataset-driven and architecture-driven strategies. Data-driven strategies will consider the size and heterogeneity of the data, while architecture driven will focus on the distribution of the datasets. This system is based on a Grid middleware tools that integrate appropriate large data manipulation operations. Therefore, this allows more dynamicity and autonomicity during the mining, integrating and processing phases

cs.DC↗

arXiv2017

Admire framework: Distributed data mining on data grid platforms

In this paper, we present the ADMIRE architecture; a new framework for developing novel and innovative data mining techniques to deal with very large and distributed heterogeneous datasets in both commercial and academic applications. The main ADMIRE components are detailed as well as its interfaces allowing the user to efficiently develop and implement their data mining applications techniques on a Grid platform such as Globus ToolKit, DGET, etc.

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arXiv2016

Forensics Acquisition and Analysis of instant messaging and VoIP applications

The advent of the Internet has significantly transformed the daily activities of millions of people, with one of them being the way people communicate where Instant Messaging (IM) and Voice over IP (VoIP) communications have become prevalent. Although IM applications are ubiquitous communication tools nowadays, it was observed that the relevant research on the topic of evidence collection from IM services was limited. The reason is an IM can serve as a very useful yet very dangerous platform for the victim and the suspect to communicate. Indeed, the increased use of Instant Messengers on smart phones has turned to be the goldmine for mobile and computer forensic experts. Traces and Evidence left by applications can be held on smart phones and retrieving those potential evidences with right forensic technique is strongly required. Recently, most research on IM forensics focus on applications such as WhatsApp, Viber and Skype. However, in the literature, there are very few forensic analysis and comparison related to IM applications such as WhatsApp, Viber and Skype and Tango on both iOS and Android platforms, even though the total users of this application already exceeded 1 billion. Therefore, in this paper we present forensic acquisition and analysis of these four IMs and VoIPs for both iOS and Android platforms. We try to answer on how evidence can be collected when IM communications are used. We also define taxonomy of target artefacts in order to guide and structure the subsequent forensic analysis. Finally, a review of the information that can become available via the IM vendor was conducted. The achieved results of this research provided elaborative answers on the types of artifacts that can be identified by these IM and VoIP applications. We compare moreover the forensics analysis of these popular applications: WhatApp, Skype, Viber and Tango.

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arXiv2016

Toward a new mobile cloud forensic framework

Smartphones have created a significant impact on the day to day activities of every individual. Now a days a wide range of Smartphone applications are available and it necessitates high computing resources in order to build these applications. Cloud computing offers enormous resources and extends services to resource-constrained mobile devices. Mobile Cloud Computing is emerging as a key technology to utilize virtually unlimited resources over the Internet using Smartphones. Offloading data and computations to improve productivity, enhance performance, save energy, and improve user experience. Social network applications largely utilize Mobile Cloud Computing to reap the benefits. The social network has witnessed unprecedented growth in the recent years, and millions of registered users access it using Smartphones. The mobile cloud social network applications introduce not only convenience but also various issues related to criminal and illegal activities. Despite being primarily used to communicate and socialize with contacts, the multifarious and anonymous nature of social networking websites increases susceptibility to cybercrimes. Taking into account, the advantage of mobile cloud computing and popularity of social network applications, it is essential to establish a forensic framework based on mobile cloud platform that solves the problems of today forensic requirements. In this paper we present a mobile cloud forensic framework that allows the forensic investigator to collect the automated synchronized copies of data on both mobile and cloud servers to prove the evidence of cloud usage. We also show our preliminary results of this study.

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arXiv2016

The State of the Art Forensic Techniques in Mobile Cloud Environment: A Survey, Challenges and Current Trends

Smartphones have become popular in recent days due to the accessibility of a wide range of applications. These sophisticated applications demand more computing resources in a resource constraint smartphone. Cloud computing is the motivating factor for the progress of these applications. The emerging mobile cloud computing introduces a new architecture to offload smartphone and utilize cloud computing technology to solve resource requirements. The popularity of mobile cloud computing is an opportunity for misuse and unlawful activities. Therefore, it is a challenging platform for digital forensic investigations due to the non-availability of methodologies, tools and techniques. The aim of this work is to analyze the forensic tools and methodologies for crime investigation in a mobile cloud platform as it poses challenges in proving the evidence. The advancement of forensic tools and methodologies are much slower than the current technology development in mobile cloud computing. Thus, forces the available tools, and techniques become increasingly obsolete. Therefore, it opens up the door for the new forensic tools and techniques to cope up with recent developments. Hence, this work presents a detailed survey of forensic methodology and corresponding issues in a mobile device, cloud environment, and mobile cloud applications. It mainly focuses on digital forensic issues related to mobile cloud applications and also analyze the scope, challenges and opportunities. Finally, this work reviewed the forensic procedures of two cloud storage services used for mobile cloud applications such as Dropbox and SkyDrive.

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arXiv2016

Forensics Acquisition of IMVU: A Case Study

There are many applications available for personal computers and mobile devices that facilitate users in meeting potential partners. There is, however, a risk associated with the level of anonymity on using instant message applications, because there exists the potential for predators to attract and lure vulnerable users. Today Instant Messaging within a Virtual Universe (IMVU) combines custom avatars, chat or instant message (IM), community, content creation, commerce, and anonymity. IMVU is also being exploited by criminals to commit a wide variety of offenses. However, there are very few researches on digital forensic acquisition of IMVU applications. In this paper, we discuss first of all on challenges of IMVU forensics. We present a forensic acquisition of an IMVU 3D application as a case study. We also describe and analyse our experiments with this application.

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arXiv2016

Android and Wireless data-extraction using Wi-Fi

Today, mobile phones are very popular, fast growing technology. Mobile phones of the present day are more and more like small computers. The so-called "smartphones" contain a wealth of information each. This information has been proven to be very useful in crime investigations, because relevant evidence can be found in data retrieved from mobile phones used by criminals. In traditional methods, the data from mobile phones can be extracted using an USB-cable. However, for some reason this USB-cable connection cannot be made, the data should be extracted in an alternative way. In this paper, we study the possibility of extracting data from mobile devices using a Wi-Fi connection. We describe our approach on mobile devices containing the Android Operating System. Through our experiments, we also give recommendation on which application and protocol can be used best to retrieve data.

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arXiv2015

Project Maelstrom: Forensic Analysis of the BitTorrent-Powered Browser

In April 2015, BitTorrent Inc. released their distributed peer-to-peer powered browser, Project Maelstrom, into public beta. The browser facilitates a new alternative website distribution paradigm to the traditional HTTP-based, client-server model. This decentralised web is powered by each of the visitors accessing each Maelstrom hosted website. Each user shares their copy of the website's source code and multimedia content with new visitors. As a result, a Maelstrom hosted website cannot be taken offline by law enforcement or any other parties. Due to this open distribution model, a number of interesting censorship, security and privacy considerations are raised. This paper explores the application, its protocol, sharing Maelstrom content and its new visitor powered "web-hosting" paradigm.

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arXiv2015

HTML5 Zero Configuration Covert Channels: Security Risks and Challenges

In recent months there has been an increase in the popularity and public awareness of secure, cloudless file transfer systems. The aim of these services is to facilitate the secure transfer of files in a peer-to- peer (P2P) fashion over the Internet without the need for centralised authentication or storage. These services can take the form of client installed applications or entirely web browser based interfaces. Due to their P2P nature, there is generally no limit to the file sizes involved or to the volume of data transmitted - and where these limitations do exist they will be purely reliant on the capacities of the systems at either end of the transfer. By default, many of these services provide seamless, end-to-end encryption to their users. The cybersecurity and cyberforensic consequences of the potential criminal use of such services are significant. The ability to easily transfer encrypted data over the Internet opens up a range of opportunities for illegal use to cybercriminals requiring minimal technical know-how. This paper explores a number of these services and provides an analysis of the risks they pose to corporate and governmental security. A number of methods for the forensic investigation of such transfers are discussed.

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arXiv2015

Network investigation methodology for BitTorrent Sync: A Peer-to-Peer based file synchronisation service

High availability is no longer just a business continuity concern. Users are increasingly dependant on devices that consume and produce data in ever increasing volumes. A popular solution is to have a central repository which each device accesses after centrally managed authentication. This model of use is facilitated by cloud based file synchronisation services such as Dropbox, OneDrive, Google Drive and Apple iCloud. Cloud architecture allows the provisioning of storage space with "always-on" access. Recent concerns over unauthorised access to third party systems and large scale exposure of private data have made an alternative solution desirable. These events have caused users to assess their own security practices and the level of trust placed in third party storage services. One option is BitTorrent Sync, a cloudless synchronisation utility provides data availability and redundancy. This utility replicates files stored in shares to remote peers with access controlled by keys and permissions. While lacking the economies brought about by scale, complete control over data access has made this a popular solution. The ability to replicate data without oversight introduces risk of abuse by users as well as difficulties for forensic investigators. This paper suggests a methodology for investigation and analysis of the protocol to assist in the control of data flow across security perimeters.

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arXiv2014

BitTorrent Sync: Network Investigation Methodology

The volume of personal information and data most Internet users find themselves amassing is ever increasing and the fast pace of the modern world results in most requiring instant access to their files. Millions of these users turn to cloud based file synchronisation services, such as Dropbox, Microsoft Skydrive, Apple iCloud and Google Drive, to enable "always-on" access to their most up-to-date data from any computer or mobile device with an Internet connection. The prevalence of recent articles covering various invasion of privacy issues and data protection breaches in the media has caused many to review their online security practices with their personal information. To provide an alternative to cloud based file backup and synchronisation, BitTorrent Inc. released an alternative cloudless file backup and synchronisation service, named BitTorrent Sync to alpha testers in April 2013. BitTorrent Sync's popularity rose dramatically throughout 2013, reaching over two million active users by the end of the year. This paper outlines a number of scenarios where the network investigation of the service may prove invaluable as part of a digital forensic investigation. An investigation methodology is proposed outlining the required steps involved in retrieving digital evidence from the network and the results from a proof of concept investigation are presented.

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arXiv2014

The Case for a Collaborative Universal Peer-to-Peer Botnet Investigation Framework

Peer-to-Peer (P2P) botnets are becoming widely used as a low-overhead, efficient, self-maintaining, distributed alternative to the traditional client/server model across a broad range of cyberattacks. These cyberattacks can take the form of distributed denial of service attacks, authentication cracking, spamming, cyberwarfare or malware distribution targeting on financial systems. These attacks can also cross over into the physical world attacking critical infrastructure causing its disruption or destruction (power, communications, water, etc.). P2P technology lends itself well to being exploited for such malicious purposes due to the minimal setup, running and maintenance costs involved in executing a globally orchestrated attack, alongside the perceived additional layer of anonymity. In the ever-evolving space of botnet technology, reducing the time lag between discovering a newly developed or updated botnet system and gaining the ability to mitigate against it is paramount. Often, numerous investigative bodies duplicate their efforts in creating bespoke tools to combat particular threats. This paper outlines a framework capable of fast tracking the investigative process through collaboration between key stakeholders.

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arXiv2014

Digital Evidence Bag Selection for P2P Network Investigation

The collection and handling of court admissible evidence is a fundamental component of any digital forensic investigation. While the procedures for handling digital evidence take much of their influence from the established policies for the collection of physical evidence, due to the obvious differences in dealing with non-physical evidence, a number of extra policies and procedures are required. This paper compares and contrasts some of the existing digital evidence formats or "bags" and analyses them for their compatibility with evidence gathered from a network source. A new digital extended evidence bag is proposed to specifically deal with evidence gathered from P2P networks, incorporating the network byte stream and on-the-fly metadata generation to aid in expedited identification and analysis.

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arXiv2014

BitTorrent Sync: First Impressions and Digital Forensic Implications

With professional and home Internet users becoming increasingly concerned with data protection and privacy, the privacy afforded by popular cloud file synchronisation services, such as Dropbox, OneDrive and Google Drive, is coming under scrutiny in the press. A number of these services have recently been reported as sharing information with governmental security agencies without warrants. BitTorrent Sync is seen as an alternative by many and has gathered over two million users by December 2013 (doubling since the previous month). The service is completely decentralised, offers much of the same synchronisation functionality of cloud powered services and utilises encryption for data transmission (and optionally for remote storage). The importance of understanding BitTorrent Sync and its resulting digital investigative implications for law enforcement and forensic investigators will be paramount to future investigations. This paper outlines the client application, its detected network traffic and identifies artefacts that may be of value as evidence for future digital investigations.

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