Erik Buchmann

Erik Buchmann
Hochschule für Telekommunikation Leipzig | HfTL · Angewandte Informatik

Professor

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84
Publications
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548
Citations

Publications

Publications (84)
Conference Paper
Full-text available
The ongoing COVID-19 pandemic increases the need to transfer employees into home offices. Securing a home office is challenging. Approaches, such as BSI Grundschutz, ISO 2700x, NIST 800-53 or ISIS12 focus on company premises, and the data carried outside must be strongly restricted. The focus of such approaches is to secure the IT-infrastructure on...
Conference Paper
Full-text available
Without a precise specification, an IT project might not remain on time and on budget constraints, or it might lead to a different outcome than desired. A number of established standards define how requirements must be written to avoid such issues. This paper describes our ongoing work to derive a comprehensive set of standardized criteria that IT-...
Conference Paper
Full-text available
Orchestrated container virtualization, such as Docker/Kubernetes, is an attractive option to transfer complex IT ecosystems into the cloud. However, this is associated with new challenges for IT security. A prominent option to secure IT infrastructures is to use security guidelines from agencies, such as Germany's Federal Office for Information Se...
Conference Paper
Full-text available
Botnets, such as Mirai or Reaper show that many Smart Home devices are low-hanging fruits for attackers. Nevertheless , it is an ongoing trend to replace everyday devices, such as TV, fridges or doorbells by smart successors. Thus, securing Smart Homes operated by private users remains an open issue. In this paper, we explore options to integrate a...
Conference Paper
Full-text available
The Internet of Things is a result of decades of research in Ubiquitous Computing and Mobile Computing. It comes with many advantages for businesses, industry and consumers. Typical examples are a seamless integration of physical objects into digital workflows and improved modes of use for consumer products. However, if non-smart devices are replac...
Preprint
Full-text available
Die Umsetzung der aktuellen Datenschutz-Normen ist gerade für große, international agierende Unternehmen mit unterschiedlichen Geschäftsfeldern eine Herausforderung. Komplexe, miteinander verflochtene Unternehmensprozesse und länderübergreifende Organisationsstrukturen erschweren die Implementierung von Datenschutzmaßnahmen. Das im April 2020 in de...
Chapter
Full-text available
The General Data Protection Regulation (GDPR) strengthens the importance of data privacy and protection for enterprises offering their services in the EU. An important part of intensified efforts towards better privacy protection is enterprise workflow (re)design. In particular, the GDPR has strengthened the imperative to apply the privacy by desig...
Conference Paper
Full-text available
Die Container-Virtualisierung baut auf eine komplexe IT-Landschaft auf, in der Hardware, Betriebssystem und Anwendungen von verschiedenen Parteien bereitgestellt und genutzt werden. Der IT-Sicherheit kommt daher eine große Bedeutung zu. Es gibt jedoch wenig Erfahrung mit der Absicherung der Container-Virtualisierung: Das Grundschutz-Kompendium und...
Conference Paper
Full-text available
With the advent of the Internet of Things (IoT), many domestic devices have been equipped with information technology. By connecting IoT devices with each other and with the Internet, Smart Home installations exist that allow the automation of complex household tasks. A popular example is Google Nest that controls cooling, heating and home security...
Article
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Zusammenfassung Das Auskunftsersuchen nach Art. 15 DSGVO bietet einiges Neues im Vergleich zum alten BDSG. Wir haben in einer Studie stichprobenhaft untersucht, auf welche Art und Weise prominente Online-Händler und Dienstleistungsunternehmen kurz nach dem Scharfstellen der DSGVO auf Auskunftsersuchen reagiert haben – mit überraschenden Erkenntniss...
Conference Paper
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Im Zuge einer Mobilitätswende werden Konzepte der multimodalen Mobilität immer wichtiger. Multimodale Mobilität bedeutet, dass dem Nutzer in Abhängigkeit von persönlichen und externen Faktoren eine Kombination aus Reisemitteln angeboten, gebucht und abgerechnet wird, die sein Mobilitätsbedürfnis erfüllen. Zu den persönlichen Faktoren zählen Präfere...
Conference Paper
Full-text available
Das Bundesamt für Sicherheit in der Informationstechnik (BSI) stellt mit dem IT-Grundschutz eine sichere und wirksame Schutzvorkehrung vor den stetig steigenden Bedrohungen im Kontext der Digitalisierung zur Verfügung. Zwar sind die behandelten BSI-Bausteine herstellerneutral definiert. Gleichwohl beziehen sich die Bausteine auf die sich ändernden...
Conference Paper
Full-text available
Aufgrund der Digitalisierung von Geschäftsprozessen werden immer mehr personenbezogene Daten von computergestützten Informationssystemen erfasst, gespeichert und verarbeitet. Deshalb steigen die Anforderungen an Unternehmen bezüglich der Umsetzung von Datenschutzregelungen. Workflow Privacy Patterns (WPP) haben das Potenzial, Unternehmen bei dieser...
Conference Paper
Full-text available
Voice assistants like Amazon Alexa, Google Assistant or Siri are becoming increasingly popular. Such assistants allow for complex interactions with smart Internet-of-Things (IoT) devices that do not have a traditional user interface, such as monitor and keyboard. However, while voice assistants foster the proliferation of numerous convenient servic...
Conference Paper
Full-text available
Workflow design patterns provide abstract, "best-practices" solutions to recurring problems. While the majority of workflow patterns focus on control flow, resources and data, our concern are patterns from a data privacy perspective. Privacy patterns have the potential to ease the life of process developers, auditors and privacy officers by providi...
Conference Paper
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Microgrids are local energy distribution cells that include energy consumers and energy generators and may or may not be connected to wide-area transmission grids. By balancing consumption and supply locally, microgrids foster the transition to renewable energy sources that are less predictable than carbon-based ones. In this context, an important...
Article
To ease the proliferation of big data, it frequently is transformed, be it by compression, be it by anonymization. Such transformations however modify characteristics of the data. In the case of time series, important characteristics are the occurrence of certain changes or patterns in the data, also referred to as events. Clearly, the less transfo...
Article
Full-text available
Wireless sensor networks (WSNs) have become ubiquitous, e.g., in logistics, smart manufacturing, smart city infrastructures or vehicular ad-hoc networks. WSNs tend to rely on ad-hoc infrastructures that are prone to a wide range of different defects, e.g., communication failures, faulty sensors or nodes that have been tampered with. Additionally, d...
Article
Today, time series of numerical data are ubiquitous, for instance in the Internet of Things. In such scenarios, it is often necessary to compress the data to, say, reduce data-transmission costs, and to detect changes on it. More specifically, both methods are used in combination, i.e., data is lossily compressed and later decompressed, and then ch...
Conference Paper
The global energy transition requires the availability of energy-consumption data with high resolution. Smart meters record such data in real time. This however endangers privacy: Time series of energy-consumption data contain different kinds of private information, such as the employment status of the residents. We address this problem by proposin...
Conference Paper
Outsourcing databases has numerous advantages over hosting traditional servers in-house. However, data containing business secrets or personal information cannot be outsourced to external service providers unprotected. A number of formal frameworks for query processing on encrypted data have been proposed to solve this challenge. However, these fr...
Article
Wann ist ein Datenbestand so anonymisiert, dass ein Personenbezug tatsächlich nicht mehr hergestellt werden kann? Welche Merkmale sind es, mit denen Einzelangaben einem Betroffenen zugeordnet werden können? Und kann ein Neugieriger tatsächlich keine persönlichen Informationen aus einem anonymisierten Datenbestand erfahren? Der Beitrag stellt vor, w...
Conference Paper
To ease the proliferation of big data, it frequently is transformed, be it by compression, be it by anonymization. Such transformations however modify characteristics of the data, such as changes in the case of time series. Changes however are important for subsequent analyses. The impact of those modifications depends on the application scenario,...
Article
Many recent applications depend on time series of data containing personal information. For example, the smart grid collects and distributes time series of energy-consumption data from households. Our concern is information hiding in such data according to individual privacy constraints, considering several constraints at a time. The existing infor...
Article
Full-text available
Many application domains such as surveillance, environmental monitoring or sensor-data processing need upper and lower bounds on areas that are covered by a certain feature. For example, a smart-city infrastructure might need bounds on the size of an area polluted with fine-dust, to re-route combustion-engine traffic. Obtaining such bounds is chall...
Article
Many application areas, e.g., demand response, energy accounting or energy-aware scheduling, require estimates of the energy consumption of computer systems. However, existing estimation approaches often make restrictive assumptions regarding the effort at setup time or run time that is acceptable, they are tailored for specific hardware or softwar...
Conference Paper
In past years, many anonymization schemes, anonymity notions, and anonymity measures have been proposed. When designing information systems that feature anonymity, choosing a good approach is a very important design choice. While experiments comparing such approaches are enlightening, carrying out such experiments is a complex task and is labor-int...
Article
Data management can now be outsourced to cloud service providers like Amazon Web Services or IBM SmartCloud. This calls for encrypted data-representation schemes that also give way to efficient query processing. State-of-the-art approaches are overly expensive for exact-match queries in the worst case, or they do not ensure privacy if an adversary...
Conference Paper
Many renewable sources for electricity generation are distributed and volatile by nature, and become inefficient and difficult to coordinate with traditional power transmission paths. As a part of the transition from fossil fuel to renewable sources, local energy markets allow an efficient allocation and distribution of energy from local sources to...
Conference Paper
Location-Based Services (LBS) are becoming more prevalent. While there are many benefits, there are also real privacy risks. People are unwilling to give up the benefits - but can we reduce privacy risks without giving up on LBS entirely? This paper explores the possibility of introducing uncertainty into location information when using an LBS, so...
Article
The Smart Grid approach enhances the power grid with information technology. Smart Meters are an important part of the Smart Grid. They record the energy consumption of households with a high-resolution and transfer consumption records to the energy provider in real time. Since they allow to infer personal information like the daily routine of the...
Article
Full-text available
Wireless sensor networks (WSN) are deployed to detect, monitor and track environmental phenomena such as toxic clouds or dense areas of air pollution in an urban environment. Most phenomena are often modeled as 2D objects (e.g., a fire region based on ...
Conference Paper
In the recent past, there have been frequent reports on privacy violations by service providers on the Web. The providers are overstrained with the legal implications of processing personal data. Data-protection authorities in turn are overburdened with the enforcement of the regulations. Users themselves typically cannot identify those violations,...
Conference Paper
Many popular web sites use folksonomies to let people label objects like images (Flickr), music (Last.fm), or URLs (Delicous) with schema-free tags. Folksonomies may reveal personal information. For example, tags can contain sensitive information, the set of tagged objects might disclose interests, etc. While many users call for sophisticated priva...
Article
Impact assessment (IA) is a key method for the legislator to evaluate policies, norms or regulations currently under development. Experts use IA to gather and analyze input from many individuals to obtain clear problem statements, estimations regarding policies etc., and use this information to compare policy alternatives. Currently, the opinions,...
Article
Recently, a number of query processors has been proposed for the evaluation of relational queries in structured P2P systems. However, as these approaches do not consider peer or link failures, they cannot be deployed without extensions for real-world applications. We show that typical failures in structured P2P systems can have an unpredictable imp...
Conference Paper
Tracking moving objects in relation to regions of interest, e.g., for pollution control or habitat monitoring, is an important application of Sensor Networks (SN). Research on Moving Object Databases has resulted in sophisticated mechanisms for querying moving objects and regions declaratively. Applying these results to SN in a straightforward way...
Conference Paper
While join processing in wireless sensor networks has received a lot of attention recently, current solutions do not work well for continuous queries. In those networks however, continuous queries are the rule. To minimize the communication costs of join processing, it is important to not ship non-joining tuples. In order to know which tuples do no...
Conference Paper
While data privacy is a human right, it is challenging to enforce it. For example, if multiple retailers execute a single order at Amazon Marketplace, each retailer can use different agencies for shipment, payment etc., resulting in unmanageable flows of personal data. In this work, we present the Privacy 2.0 system, which enables people to share e...
Article
Full-text available
Specifying information needs declaratively has turned out to be useful in the context of databases systems, and reseachers have applied this approach to sensor networks. The first step to retrieve data from a sensor network in this way is the dissemination of the query. Energy-efficient query dissemination plays an important role for the lifetime o...
Conference Paper
In retail, products are organized according to layout plans, so-called planograms. Compliance to planograms is important, since good product placement can significantly increase sales. Currently, retailers are about to implement RFID installations consisting of smart shelves and RFID-tagged items to support in-store logistics and processes. In prin...
Book
The amount and value of information available due to rapid spread of information technology is exploding. Typically, large enterprises have approximately a petabyte of operational data stored in hundreds of data repositories supporting thousands of applications. Data storage volumes grow in excess of 50% annually. This growth is expected to con...
Article
Full-text available
Research on Moving Object Databases (MOD) has resulted in sophisticated query mechanisms for moving objects and regions. Wireless Sensor Networks (WSN) support a wide range of applications that track or monitor moving objects. However, applying the concepts of MOD to WSN is difficult: While MOD tend to require precise object positions, the informat...
Article
Full-text available
Software regelt immer mehr zwischenmenschliche Interaktionen. Üblicherweise werden die Funktionsmechanismen, Wirkungen und Gestaltungsoptionen von Regeln in der Institutionenforschung behandelt. In diesem Artikel soll beleuchtet werden, inwieweit sich Ansätze der Institutionenforschung auf Software anwenden lassen und was sich aus dieser Forschungs...
Conference Paper
Location based services (LBS) let people retrieve and share information related to their current position. Examples are Google Latitude or Panoramio. Since LBS share user-related content, location information etc., they put user privacy at risk. Literature has proposed various privacy mechanisms for LBS. However, it is unclear which mechanisms huma...
Conference Paper
Full-text available
Data privacy is a fundamental human right, not only according to the EU perspective. Each EU state implements sophisticated data protection acts. Nevertheless, there are frequent media reports on data privacy violations. The scientific and the political community assume that data protection acts suffer from a lack of enforcement. This paper is an i...
Article
Answering queries with a low selectivity in wireless sensor net- works is a challenging problem. A simple tree-based data col- lection is communication-intensive and costly in terms of energy. Prior work has addressed the problem by approximating query re- sults based on models of sensor readings. This cuts communication effort if the accuracy requ...
Conference Paper
Join processing in wireless sensor networks is dif- ficult: As the tuples can be arbitrarily distributed within the network, matching pairs of tuples is communication intensive and costly in terms of energy. Current solutions only work well with specific placements of the nodes and/or make restrictive assumptions. In this paper, we present SENS-Joi...
Conference Paper
Collaborative search engines (CSE) are an upcoming trend in WWW search. CSE let knowledge workers concert their efforts and support user collaboration. However, search terms and links clicked that are shared among users reveal their interests, habits, social relations and intentions. Thus, CSE might put the privacy of the users at risk. In this pap...
Conference Paper
Full-text available
Impact assessment (IA) is a key method for the legislator to evaluate policies, norms or regulations currently under development. Experts use IA to gather and analyze input from many individuals to obtain clear problem statements, estimations regarding policies etc., and use this information to compare policy alternatives. Currently, the opinions,...
Conference Paper
Full-text available
Materialized views (MV) can significantly improve the query performance of relational databases. In this paper, we con- sider MVs to optimize complex scenarios where many het- erogeneous nodes with dierent resource constraints (e.g., CPU, IO and network bandwidth) query and update nu- merous tables on dierent nodes. Such problems are typical for la...
Conference Paper
A growing number of users in Web 2.0 based social network sites and photo sharing portals upload millions of images per day. In many cases, this leads to serious privacy threats. The images reveal not only the personal relationships and attitudes of the uploader, but of other persons displayed in the images as well. In this paper, we propose the PR...
Conference Paper
Full-text available
Collaborative search engines (CSE) let users pool their re- sources and share their experiences when seeking information on the web. However, when shared, search terms and links clicked reveal user interests, habits, social relations and intentions. In other words, CSE put privacy of users at risk. This seriously limits the proliferation and accep-...
Conference Paper
Full-text available
Energy-efficient query dissemination plays an important role for the lifetime of sensor networks. In this work, we consider probabilistic flooding for query dissemination and develop an analytical framework which enables the base station to predict the energy consumed and the nodes reached according to the rebroadcast probability. Furthermore, we d...
Conference Paper
Radio Frequency Identification (RFID) promises optimization of commodity flows in all industry segments. But due to physical constraints, RFID technology cannot detect all RFID tags from an assembly of items. This poses problems when integrating RFID data with enterprise-backend systems for tasks like inventory management or shelf replenishment. In...
Conference Paper
Application areas like semantic caches or update relevancy checks require query based indexing: They use an algebra representation of the query tree to identify reusable fragments of former query results. This requires compact query representations, where semantically equivalent (sub-)queries are expressed with identical terms. It is challenging to...
Article
Full-text available
Web2.0 applications have become an inherent part of everyday life, with unpredictable consequences for the privacy of individuals. People communicate via social network sites and participate in the life of others by commenting blogs or tagging web sites, images or videos. Specialized search engines can assemble this information to comprehensive per...
Article
Research on P2P data structures has tacitly as- sumed that peers readily participate in the work, i.e., are c o- operative. But such participation is voluntary, and free ri d- ing is the dominant strategy. This article describes a proto col that renders free riding unattractive, for one particular P 2P data structure. The protocol is based on feedb...
Conference Paper
Most of the approaches for ad hoc networks assume that the nodes readily and honestly follow the protocol. Unfortunately, this assumption does not always hold in reality. Misbehaving in ad hoc networks can take place at different levels of the system architecture: 1 On the communication level, nodes can refuse to forward messages of others in orde...
Conference Paper
Peer-to-Peer data structures (P2P data structures) let a la rge number of anonymous peers share the data-management workload. A common assump- tion behind such systems is that peers behave cooperatively. But as with many distributed systems where participation is voluntary, and the participants are not clearly observable, unreliable behavior is the...
Chapter
If an environment depends on the services of a multiagent system it should do so only if it can justifiably place reliance on this service. If so, the system appears to the environment reliable, or dependable. It is well-known that dependability should be designed right into a system rather than added as an afterthought. Particularly due to the hig...
Article
Full-text available
Peer-to-Peer (P2P) Data Structures (a.k.a. P2P Overlays or Structured P2P Networks) are able to administer huge sets of (key,value)-pairs and cope with many parallel requests. By following the P2P paradigm, P2P Data Structures distribute the data set and the workload among all participants. In general, approaches for P2P data structures assume that...
Article
The aim of this article is to examine the relationship of large-scale Peer-to-Peer (P2P) overlay networks and certain biological systems. In particular, we focus on organization mechanisms that are crucial to adjust and optimize the behavior of large-scale P2P systems in the face of a dynamic environment. We propose to adopt concepts and mechanisms...
Conference Paper
Full-text available
Distributed hash tables (DHTs) promise to manage huge sets of key-value pairs in a peer-to-peer manner. The content-addressable network (CAN) is a prominent variant of DHT. A critical challenge when designing a CAN, or indeed any DHT, is ensuring that all data items are accessible despite the presence of malicious and faulty peers. Such peers may h...
Conference Paper
Full-text available
Structured P2P systems in the form of distributed hash tables (DHT) are a promising approach for building massively distributed data management platforms. However, for many applications the supported key lookup queries are not sufficient. Instead, techniques for managing and querying (relational) structured data are required. In this paper, we argu...
Conference Paper
Full-text available
Peer-to-Peer (P2P)-Systeme und hierbei speziell verteilte Datenstrukturen versprechen Skalierbarkeit bis auf Internet-Größe bei fairer Verteilung der Infrastruk- turkosten und hoher Robustheit. Für viele potenzielle Anwendungen sind die von der- artigen Systemen unterstützten einfachen Schlüsselzugriffe nicht ausreichend - viel- mehr ist die Verwal...
Conference Paper
Content-Addressable Networks (CAN) are able to manage huge sets of (key,value)-pairs and cope with very high workloads. They follow the peer-to-peer (P2P) paradigm in order to build scalable, distributed data structures on top of the Internet. CAN are designed to drive Internet-scale applications like distributed search engines, multimedia retrieva...
Conference Paper
Content-Addressable Networks (CAN) manage huge sets of (key, va- lue)-pairs and cope with very high workloads. They follow the peer-to-peer pa- radigm: They consist of nodes that are autonomous. This means that peers may be uncooperative, i.e., not carrying out their share of the work while trying to benefit from the network. This article deals wit...
Conference Paper
Full-text available
Summary form only given. Distributed hash tables (DHT) promise to administer huge sets of (key, value)-pairs under high workloads. DHT currently are a hot topic of research in various disciplines of computer science. Experimental results that are convincing require evaluations with large DHT (i.e., more than 100,000 nodes). However, many studies co...
Conference Paper
Full-text available
Verteilte skalierbare Datenstrukturen (SDDS) besitzen große Bedeutung, insbesondere als Grundlage der Realisierung von innovativen Web-Diensten. Die Kno- ten einer SDDS verwalten (Schl¨ ussel, Wert)-Paare sowie Kontaktinformation ¨ uber an- dere Knoten. Diese Kontaktinformationen werden fur das Routing von Nachrichten zwischen den SDDS-Knoten ben¨...
Conference Paper
The increasing usage of mobile devices like PDAs, laptops, or embedded devices results in a new type of application which must especially consider the strict limitations of the used mobile hardware. One as- pect of the application development is the storage and retrieval of data. For non-mobile application this is often efficiently realized with da...
Article
Full-text available
Distributed hash-tables (DHTs) are peer-to-peer overlay networks that are primarily used for dis-tributed data storage. While there are several design variants of DHTs, including the Content-Addressable Network (CAN), Chord, and Pastry, all promise to be self-organizing, fault-resistant, and highly scalable. However, most of the proposed protocols...
Article
28. März 2002 Zusammenfassung Durch den zunehmenden Einsatz von mobilen Geräten gewinnen mobile Anwendungen vermehrt an Bedeutung. Ein wesentlicher Aspekt dieser Anwendungen ist die effiziente und flexible Daten-haltung. Für stationäre Geräte haben sich dafür Datenbankmanagement-Systeme (DBMS) vielfach bewährt; diese berücksichtigen jedoch nicht di...
Article
Übersicht. Immer neue Möglichkeiten der personalisierten Datensammlung machen es erforderlich, die Privatsphäre des Einzelnen speziell in der IT-Welt zu schützen. Im Rahmen des Seminars "Informationsverwaltung in Sensornetzwerken" befasst sich diese Arbeit mit verschiedenen Ansätzen, Privatheit durch Manipulation der Datenqualität zu gewährleisten....
Article
Full-text available
In this paper we present initial results of our efforts to build a distributed query engine for a Peer- to-Peer system implementing a distributed hash table (DHT). Based on a discussion of requirements to process SQL-like queries we describe our extensions to the DHT API and discuss data fragmen- tation issues. We show the realization of a physical...
Article
Full-text available
Data acquisition in battery-powered sensor networks must be energy-efficient. Given this objective, we study the following problem: At which network node(s) should a join be computed? One alternative is centralized, i.e., at one location, vs. distributed. The problem with centralized approaches is that they must consolidate the data from the entire...
Conference Paper
Full-text available
Data protection is challenging in scenarios where numerous devices collect personal data without drawing attention from the individual concerned, e.g., in Ubiquitous Computing applications, Sensor Networks or Radio Frequency Identification installations. Technicalmechanisms for data protection force the individual to keep track of his personal data...