Max Mühlhäuser

Towards a Trust Management System for Cloud Computing

Cloud computing provides cost-efficient opportunities for enterprises by offering a variety of dynamic, scalable, and shared services. Usually, cloud providers provide assurances by specifying technical and functional descriptions in Service Level Agreements (SLAs) for the services they offer. The descriptions in SLAs are not consistent among the cloud providers even though they offer services with similar functionality. Therefore, customers are not sure whether they can identify a trustworthy cloud provider only based on its SLA. To support the customers in reliably identifying trustworthy cloud providers, we propose a multi-faceted Trust Management (TM) system architecture for a cloud computing marketplace. This system provides means to identify the trustworthy cloud providers in terms of different attributes (e.g., security, performance, compliance) assessed by multiple sources and roots of trust information.

Cloud Computing Landscape and Research Challenges Regarding Trust and Reputation

Cloud Computing is an emerging computing paradigm. It shares massively scalable, elastic resources (e.g., data, calculations, and services) transparently among the users over a massive network. The Cloud market is growing rapidly and bringing up numerous research challenges. This paper provides a landscape of Cloud Computing and its research challenges, especially considering the areas of service selection, quality assurance of Cloud services, and trust establishment in Cloud environments. As the latter is known to be one of the major challenges of Cloud Computing, We also provide an overview of the important aspects that need to be considered when integrating trust and reputation concepts into Cloud Computing.

MundoCore: A light-weight infrastructure for pervasive computing

MundoCore is a communication middleware specifically designed for the requirements of pervasive computing. To address the high degree of heterogeneity of platforms and networking technologies, it is based on a microkernel design, supports dynamic reconfiguration, and provides a common set of APIs for different programming languages (Java, C++, Python) on a wide range of different devices. The architectural model addresses the need for proper language bindings, different communication abstractions, peer-to-peer overlays, different transport protocols, different invocation protocols, and automatic peer discovery.

Trust as a facilitator in cloud computing: a survey

AbstractCloud computing offers massively scalable, elastic resources (e.g., data, computing power, and services) over the internet from remote data centres to the consumers. The growing market penetration, with an evermore diverse provider and service landscape, turns Cloud computing marketplaces a highly competitive one. In this highly competitive and distributed service environment, the assurances are insufficient for the consumers to identify the dependable and trustworthy Cloud providers.This paper provides a landscape and discusses incentives and hindrances to adopt Cloud computing from Cloud consumers’ perspective. Due to these hindrances, potential consumers are not sure whether they can trust the Cloud providers in offering dependable services. Trust-aided unified evaluation framework by leveraging trust and reputation systems can be used to assess trustworthiness (or dependability) of Cloud providers. Hence, cloud-related specific parameters (QoS + ) are required for the trust and reputation systems in Cloud environments. We identify the essential properties and corresponding research challenges to integrate the QoS + parameters into trust and reputation systems. Finally, we survey and analyse the existing trust and reputation systems in various application domains, characterizing their individual strengths and weaknesses. Our work contributes to understanding 1) why trust establishment is important in the Cloud computing landscape, 2) how trust can act as a facilitator in this context and 3) what are the exact requirements for trust and reputation models (or systems) to support the consumers in establishing trust on Cloud providers.

An IR local positioning system for smart items and devices

This paper describes IRIS-LPS (InfraRed Indoor Scout), an optical infrared local positioning system. The tracked objects carry active tags that emit infrared signals which are received by a stationary mounted stereo-camera. The system is based on cheap off-the-shelf components, is easy to deploy, and features a large range of coverage. It is capable of tracking a large number of tags without significant performance impact, since the sampling rate remains constant with an increasing number of tags. A test installation of the system has been evaluated in a lecture hall. The positioning system is utilized by our audio-centric user terminal called Talking Assistant. This and other application scenarios are described at the end.

Tool support for the synchronization and presentation of distributed multimedia

Abstract Synchronization of multiple media is a major issue in multimedia applications; in distributed systems, this problem is aggravated further. We present tools for the creation, editing, and presentation of synchronized multimedia objects. In particular, we describe a graphical Synchronization Editor for the specification of synchronization schemes and a Synchronizer for the execution of multimedia presentations. We emphasize the requirements imposed by an underlying distributed heterogeneous environment, as well as support for interactive user control. The tools described are not restricted to a fixed set of media, but support the inclusion of arbitrary user-defined media. The Synchronization Editor and Synchronizer are part of the Mode project, which in turn covers the ‘distributed multimedia object support’ part of NESTOR, an authoring/learning environment developed jointly by the Universities of Karlsruhe and Kaiserslautern and the Digital Equipment CEC, Karlsruhe.

Taxonomy and Survey of Collaborative Intrusion Detection

The dependency of our society on networked computers has become frightening: In the economy, all-digital networks have turned from facilitators to drivers; as cyber-physical systems are coming of age, computer networks are now becoming the central nervous systems of our physical world—even of highly critical infrastructures such as the power grid. At the same time, the 24/7 availability and correct functioning of networked computers has become much more threatened: The number of sophisticated and highly tailored attacks on IT systems has significantly increased. Intrusion Detection Systems (IDSs) are a key component of the corresponding defense measures; they have been extensively studied and utilized in the past. Since conventional IDSs are not scalable to big company networks and beyond, nor to massively parallel attacks, Collaborative IDSs (CIDSs) have emerged. They consist of several monitoring components that collect and exchange data. Depending on the specific CIDS architecture, central or distributed analysis components mine the gathered data to identify attacks. Resulting alerts are correlated among multiple monitors in order to create a holistic view of the network monitored. This article first determines relevant requirements for CIDSs; it then differentiates distinct building blocks as a basis for introducing a CIDS design space and for discussing it with respect to requirements. Based on this design space, attacks that evade CIDSs and attacks on the availability of the CIDSs themselves are discussed. The entire framework of requirements, building blocks, and attacks as introduced is then used for a comprehensive analysis of the state of the art in collaborative intrusion detection, including a detailed survey and comparison of specific CIDS approaches.

CoScribe: Integrating Paper and Digital Documents for Collaborative Knowledge Work

This paper presents CoScribe, a concept and prototype system for the combined work with printed and digital documents, which supports a large variety of knowledge work settings. It integrates novel pen-and-paper-based interaction techniques that enable users to collaboratively annotate, link and tag both printed and digital documents. CoScribe provides for a very seamless integration of paper with the digital world, as the same digital pen and the same interactions can be used on paper and displays. As our second contribution, we present empirical results of three field studies on learning at universities. These motivated the design of CoScribe and were abstracted to a generic framework for the design of intuitive pen-and-paper user interfaces. The resulting interaction design comprising collaboration support and multiuser visualizations has been implemented and evaluated in user studies. The results indicate that CoScribe imposes only minimal overhead on traditional annotation processes and provides for a more efficient structuring and retrieval of documents.

iClouds – Peer-to-Peer Information Sharing in Mobile Environments

The future mobile and ubiquitous computing world will need new forms of information sharing and collaboration between people. In this paper we present iClouds, an architecture for spontaneous mobile user interaction, collaboration, and transparent data exchange. iClouds relies on wireless ad hoc peer-to-peer communications. We present the iClouds architecture and different communication models, which closely resemble familiar communication forms in the real world. We also design a hierarchical information structure for storing the information in iClouds. We present our prototype implementation of iClouds which runs on wireless-enabled PDAs.

PalmRC: imaginary palm-based remote control for eyes-free television interaction

User input on television (TV) typically requires a mediator device, such as a handheld remote control. While being a well-established interaction paradigm, a handheld device has serious drawbacks: it can be easily misplaced due to its mobility and in case of a touch screen interface, it also requires additional visual attention. Emerging interaction paradigms like 3D mid-air gestures using novel depth sensors, such as Microsofts Kinect, aim at overcoming these limitations, but are known to be e.g. tiring. In this paper, we propose to leverage the palm as an interactive surface for TV remote control. Our contribution is three-fold: (1) we explore the conceptual design space in an exploratory study. (2) Based upon these results, we investigate the effectiveness and accuracy of such an interface in a controlled experiment. And (3), we contribute PalmRC: an eyes-free, palm-surface-based TV remote control, which in turn is evaluated in an early user feedback session. Our results show that the palm has the potential to be leveraged for device-less and eyes-free TV remote interaction without any third-party mediator device.