Petra Leimich - Academia.edu (original) (raw)

Papers by Petra Leimich

Digital Investigation, Jun 1, 2019

The increasing use of encrypted data within file storage and in network communications leaves inv... more The increasing use of encrypted data within file storage and in network communications leaves investigators with many challenges. One of the most challenging is the Tor protocol, as its main focus is to protect the privacy of the user, in both its local footprint within a host and over a network connection. The Tor browser, though, can leave behind digital artefacts which can be used by an investigator. This paper outlines an experimental methodology and provides results for evidence trails which can be used within real-life investigations.

In this paper, we explore how online learning can support face-to-face teaching in fundamental da... more In this paper, we explore how online learning can support face-to-face teaching in fundamental database theory and the contributions it can make towards motivating and enhancing the student learning experience. We show how we have used WebCT for a third level database module and present student feedback to our approach. While online participation is high overall, motivation for self-learning is increased by the use of selfassessment exercises and summative assessment was also considered to be more fun online than using paper based equivalents. Evidence exists to link greater online participation of course materials to improved performance. We complement our feedback by presenting and discussing a number of software tools which help students practice important methods in database systems, including SQL. After evaluating these against known methods for improving student motivation, we suggest ideas for further development of more game-like learning tools.

This paper discusses the experience of taking part in a disciplinary commons devoted to the teach... more This paper discusses the experience of taking part in a disciplinary commons devoted to the teaching of database systems. It will discuss the structure of a disciplinary commons and our experience of the database version.

Cloud based storage is increasing in popularity, with large volumes of data being stored remotely... more Cloud based storage is increasing in popularity, with large volumes of data being stored remotely. Digital forensics investigators examining such systems remotely are limited by bandwidth constraints when accessing this kind of data using traditional tools. This paper explores the potential for sub-file hashing strategies to decrease the time taken to detect contraband on networked storage devices, while maintaining a high degree of accuracy. Results show that sub-file hashing is faster than full file hashing for both LAN and Internet server configurations, with reduced bandwidth heavily favouring sub-file strategies.

This paper evaluates the possible benefits of integrating audience response systems through mobil... more This paper evaluates the possible benefits of integrating audience response systems through mobile devices. Typically, existing clicker systems use proprietary radio remotes to send votes to a computer and display this information on screen. While proven to be a useful tool in lectures, adoption has been limited due to their upfront costs. Using mobile devices as a replacement is discussed as an alternative method by making it less intrusive and rootless. A prototype system was implemented to test these assumptions and was evaluated in a typical lecture with undergraduate students studying 'Database Fundamentals'. The students chose between this system and a typical clicker system and were asked to answer identical quizzes. While their feedback shows little benefit of the prototype over traditional systems, the mobile system offers tangible benefits to the lecturer in speeding up preparation of quizzes and setup time.

While appropriate for practical topics like SQL, our traditional format of lecture and lab fails ... more While appropriate for practical topics like SQL, our traditional format of lecture and lab fails to facilitate the discussion of more theoretical database topics with students. This paper describes and analyses the method and effects of adopting a more flexible approach with third year and postgraduate students. Some weeks use supervised labs while in others tutorials are held in seminar rooms, in smaller groups, without the distraction of computers. Requiring tutorials to be prepared in advance allows time to be used effectively, concentrating on more difficult aspects. Initial results, presented in this paper, are encouraging. Many students enjoy tutorials and exam performance has improved dramatically for some. However, as many as 25% of undergraduate students failed to attend a single tutorial, and many of those who did attend came unprepared. Could, and should, this be changed by explicitly assessing tutorials? The paper concludes by investigating approaches reported elsewhere in order to ascertain how the management of tutorials could be improved.

Digital Investigation, Sep 1, 2016

This paper discusses the challenges of performing a forensic investigation against a multi-node H... more This paper discusses the challenges of performing a forensic investigation against a multi-node Hadoop cluster and proposes a methodology for examiners to use in such situations. The procedure's aim of minimising disruption to the data centre during the acquisition process is achieved through the use of RAM forensics. This affords initial cluster reconnaissance which in turn facilitates targeted data acquisition on the identified DataNodes. To evaluate the methodology's feasibility, a small Hadoop Distributed File System (HDFS) was configured, and forensic artefacts simulated upon it by deleting data originally stored in in the cluster. RAM acquisition and analysis was then performed on the NameNode in order to test the validity of the suggested methodology. The results are cautiously positive in establishing that RAM analysis of the NameNode can be used to pinpoint the data blocks affected by the attack, allowing a targeted approach to the acquisition of data from the DataNodes, provided that the physical locations can be determined. A full forensic analysis of the DataNodes was beyond the scope of this project.

Informatik und Unternehmensführung, 1998

A new approach to the space-time modelling of infectious diseases is considered. A modulated hete... more A new approach to the space-time modelling of infectious diseases is considered. A modulated heterogeneous Poisson process with intensity defined as a function of a 2-dimensional susceptibility field is proposed. The model is fitted to a measles epidemic.

Oracle is a popular commercial database product which has been widely adopted in the teaching of ... more Oracle is a popular commercial database product which has been widely adopted in the teaching of a database related curriculum. Different Oracle packages or versions are required by various courses and other applications within the university environment. However, due to the complexity of Oracle package installation and maintenance, any attempt to install new versions of the Oracle package together with old versions and other software packages could easily cause massive conflicts in the network and operating system. Information Systems and Services (ISS) departments have been unable to provide adequate support for installing multiple or new versions of the Oracle package, which are required to teach students cutting edge practical skills for future employment. We report on teaching experiences of using Virtual Machine to overcome constraints posed by a centralised Oracle system administered by ISS. We also present three of the most widely available Virtual Machine platforms and highlight the benefits and issues of using Virtual Machine.

Traditional digital forensics processes do not scale well with the huge quantities of data presen... more Traditional digital forensics processes do not scale well with the huge quantities of data present in a modern investigation, resulting in large investigative backlogs for many law enforcement agencies. Data reduction techniques are required for fast and effective digital forensics triage, and to reduce the time taken to conduct an investigation. This work explores the potential of sub-file cryptographic hashing strategies, where small fragments of files are hashed in lieu of processing the file in its entirety, for contraband detection. Results show that subfile hashing techniques perform well, particularly on solid state media, while also retaining a high degree of discriminating power. Such strategies may offer an opportunity to take advantage of the performance characteristics of non-mechanical media, streamlining future investigations and greatly reducing investigation times.

No part of this publication may be reproduced or transmitted in any form or by any means, electro... more No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any storage and retrieval system without the written permission of the Editor. Such permission will normally be granted for educational purposes provided that due acknowledgement is given. ISBN 978-1-907207-57-0 To request copies of this report in large print or in a different format, please contact the communications office at the Higher Education Academy: 01904 717500 or pressoffice@heacademy.ac.ukFOREWORD This is the tenth in the series of highly successful international workshops on the Teaching, Learning and Assessment of Databases (TLAD 2012). TLAD 2012 is held on the 9 th July at the University of Hertfordshire and hopes to be just as successful as its predecessors. The teaching of databases is central to all Computing Science, Software Engineering, Information Systems and Information Technology courses, and this year, the w...

Higher Education Academy Subject Network for Information and Computer Sciences, Jun 28, 2010

The Journal of Digital Forensics, Security and Law, 2018

The Journal of Digital Forensics, Security and Law, 2019