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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.