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This report documents the program and the outcomes of Dagstuhl Seminar 14292 “Network Attack Detection and Defense: Securing Industrial Control Systems for Critical Infrastructures”. The main objective of the seminar was to discuss new approaches and ideas for securing
industrial control systems. It is the sequel of several previous Dagstuhl seminars: (1) the series “Network Attack Detection and Defense” held in 2008 and 2012, and (2) the Dagstuhl seminar “Securing Critical Infrastructures from Targeted Attacks”, held in 2012. At the seminar, which
brought together members from academia an industry, appropriate methods for detecting attacks on industrial control systems (ICSs) and for limiting the impact on the physical components were considered. A central question was whether and how reactive security mechanisms can be
made more ICS- and process-aware. To some extent it seems possible to adopt existing security approaches from other areas (e. g., conventional networks, embedded systems, or sensor networks). The main question is whether adopting these approaches is sufficient to reach the desired level
of security for ICSs. Detecting attacks to the physical components and appropriate reactions to attacks are new aspects that need to be considered as well. The main result of the seminar is a list of recommendations for future directions in ICS security that is presented in this report.
This paper introduces a new IEEE 802.15.4 simulation model for OMNeT++ / INET. 802.15.4 is an important underlying standard for wireless sensor networks and Internet of Things scenarios. The presented implementation is designed to be compatible with OMNeT++ 4.x and INET 2.x and laid-out to be expandable for newer revisions of the 802.15.4 standard.
We introduce the ongoing integration of Contiki’s uIP stack into the OMNeT++ port of the Network Simulation Cradle (NSC). The NSC utilizes code from real world stack implementations and allows for an accurate simulation and comparison of different TCP/IP stacks and a validation of thereby connected simulation models. uIP(v6) provides resource-constrained devices with an RFC-compliant TCP/IP stack and promotes the use of IPv6 in the vastly growing field of Internet of Things scenarios. This work-in-progress report discusses our motivation to integrate uIP into the NSC, our chosen approach and possible use cases for the simulation of uIP in OMNeT++.
Communication with smart objects currently only works in isolated, sometimes even proprietary islands. This lack of interoperability limits the value of smart objects connected to the Internet of Things (IoT). We propose to use the eXtensible Messaging and Presence Protocol (XMPP) to connect IoT islands. XMPP is inherently federated, secure, globally scalable and designed for collaboration. We use XMPP Multi-User Chat (MUC) to build a secure and accessible platform for sensor data exchange between organizations. We demonstrate a scenario of three distributed and interconnected XMPP-driven sites, whereas different client types access sensor data from all sites. Our evaluation results confirm that the architectural pattern presented in this work can easily be used in any XMPP-based system without the need to enhance or to extend the standards.
Crises such as the Fukushima incident in Japan showed the demand for flexible and easy-to-use monitoring and communication systems to support post-disaster management (i.e. the organization of actions in the follow-up of disasters), especially when critical infrastructure is affected. Such systems can effectively only be realized with a merging of various device classes and the integration of mobile actors and wireless communication technologies to provide the necessary flexibility. This article introduces a system design that combines portable hand-held devices as well as autonomous sensors through XMPP with the flexibility of cloud services to support post-disaster management. This combination provides the communication between the different involved parties (e.g., rescue teams, relief forces, NGOs) and enables a global view on sensed data through the use of cloud-based storage and analysis services. Along with a discussion about requirements and a description of appropriate solutions and initial evaluations, we present new insights on the practical appliance of XMPP and potential enhancements for XMPP-based real life collaboration applications in hybrid (ad hoc and infrastructure) networkscenarios.We also show that resource constrained devices can run the XMPP protocol to extend smartphones with sensors or to connect different device classes in a seamless way.
The increasing mobility of Internet users and the growing need to collaborate with staff travelling on business belong to the key characteristics of the future Internet. Mobile collaborative applications require novel schemes for group communication that actively support collaborations in wireless scenarios. An intrinsic problem of collaborations in wireless scenarios is the temporary connection loss with the group due to user mobility and network issues. Existing group communication protocols do not sufficiently support this situation. In this paper, we present a new peer-to-peer group communication protocol, called Moversight, that was specifically designed to support closed group cooperation in mobile environments with varying churn rates. It applies a new group communication paradigm, called mobile optimistic virtual synchrony, to handle churn-related peer failures. It enhances the virtual synchrony paradigm for mobile scenarios. The paper introduces the paradigm and describes the main protocol features of Moversight. Finally we present simulation results to demonstrate the applicability of the protocol.
Cooperation and interactions of mobile users is a characteristic feature of mobile collaborative applications. The users are located in different mobile communication networks or move in or among them, respectively. This requires horizontal and vertical handovers. The latter is required when the networks use different network technologies. Usually each mobile device independently chooses the most appropriate network for its purposes to switch to. In group-oriented applications this may lead to an uncoordinated network selection and as consequence to increased energy consumption. In this paper, we present a distributed vertical handover decision algorithm that coordinates the selection of the network among the mobile devices in order to ensure an optimal quality of service for the collaborative application and a low energy consumption of the involved mobile devices. The network selection is based on the calculation of a group benefit for each alternative network using the Simple Additive Weighting (SAW) algorithm. The feasibility of the algorithm is evaluated regarding varying group sizes and resource requirements.
Due to demographic changes in developed industrial countries and a better medical care system, the number of elderly people who still live in their home environment is rapidly growing because there they feel more comfortable and independent as in a clinical environment or in a residential care home. The elderly often live alone and receive only irregular visits. Due to impaired physical skills the probability of falls significantly increases. The detection of falls is a crucial aspect in the care of elderly. Falls are often detected very late with severe consequential damages. There are existing approaches for automatic fall detection. They usually deploy special external devices. Elderly people often do not accept these devices because they expose their frailty. In this paper, we present a location-independent fall detection method implemented as a smartphone application for an inconspicuous use in nearly every situation of the daily life. The difficulty of our approach is in the low resolution range of integrated acceleration sensors and the limited energy supply of the smartphone. As solution, we apply a modular threshold-based algorithm which uses the acceleration sensor with moderate energy consumption. Its fall detection rate is in the average of current relevant research.
A 6LoWPAN Model for OMNeT++
(2013)
Modern automation is measured in terms of interoperability and easy administration. Introducing technology focussing on these criteria, however, induce new security risks to existing and future automation installations. Current security approaches in automation do not keep pace with the rising security challenges. Prevalent in automation is the use of access control to protect the system from malicious activity, such as extern attacks. Means to inspect the automation traffic to identify attacks that already have overcome access control or are initiated from inside the automation system are not available, yet. For filling this gap, we investigate in the application of intrusion detection techniques on industrial automation. In this paper, we present the current state of an intrusion detection system tailored to the analysis of operation down to traffic between automation devices on field layer.
The increasing use of wireless networks has raised the desire to have not only a stable and good quality access to the network, but also to seamlessly change the network when moving. Various handover algorithms have been proposed to handle this situation. Unfortunately, many of these handover algorithms have only been evaluated by simulations. They do not take the wide range of mobile devices with varying system parameters into account. For the practical deployment, handover algorithms are required that adapt to various device parameters and network characteristics. In this paper we present a fuzzy-based vertical handover decision algorithm which adjusts itself to the given device and network capabilities. Starting with a discussion of handover requirements we present the algorithm and describe how it is activated in the handover process. Finally we present several experiments which evaluate the accuracy of the handover decision, the quality of service guarantees for the application, and the resource consumption.
Dualisierung graphischer Benutzeroberflächen: Portierung einer GUI vom Desktop auf Smartphone
(2012)
Protocol Engineering
(2012)
This book constitutes the refereed proceedings of the 38th Conference on Current Trends in Theory and Practice of Computer Science, SOFSEM 2012, held in Špindlerův Mlýn, Czech Republic, in January 2012.
The 43 revised papers presented in this volume were carefully reviewed and selected from 121 submissions. The book also contains 11 invited talks, 10 of which are in full-paper length. The contributions are organized in topical sections named: foundations of computer science; software and Web engineering; cryptography, security, and verification; and artificial intelligence.
The increasing dependence of human society on information technology (IT) systems requires appropriate measures to cope with their misuse. The growing potential of threats, which make these systems more and more vulnerable, is caused by the complexity of the technologies themselves. The potential of threats in networked systems will further grow as well as the number of individuals who are able to abuse these systems. It becomes increasingly apparent that IT security cannot be achieved by prevention alone. Preventive measures and reactive aspects need to complement one another. A major challenge of modern IT security technologies is to cope with an exploding variability of attacks which stems from a significant commercial motivation behind them. Increasingly proactive measures are required to ward off these threats. Increased efforts in research and society are required to protect critical civil infrastructures, such as the health care system, the traffic system, power supply, trade, military networks, and others in developed countries. This is a consequence of the increasing shift of industrial IT systems to the IP protocol leading to sensible IT infrastructures which are more vulnerable as the proprietary systems used in the past. The abundance of services of modern infrastructures critically depends on information and communication technologies. Though, being key enablers of critical infrastructures, these technologies are, at the same time, reckoned among the most vulnerable elements of the whole system. The cooperative information exchange between institutions is mandatory in order to detect distributed and coordinated attacks. Based on a large-scale acquisition of pertinent information, Early Warning Systems are a currently pursued approach to draw up situation pictures that allows the detection of trends and upcoming threats, allowing furthermore taking appropriate measures. The Dagstuhl seminar brought together researchers from academia and industry. The objective of the seminar was to further discuss challenges and methods in the area of attack detection and defense. The seminar was supposed to focus on design aspects of early warning systems and related monitoring infrastructures, e.g., intrusion detection overlays, to protect computer systems, networks, and critical infrastructures. The seminar was jointly organized by Georg Carle, Hervé Debar, Hartmut König, and Jelena Mirkovic. It was attended by 34 participants from nine countries.