3-SOS (TriSOS) - Smart Object Systems, Self-Organizing Systems, Service Oriented Systems
|Duration:||01.12.2008 - 31.12.2012|
|Project Leader:||Prof. Dr.-Ing Horst Hellbrück|
|Staff:||Joachim Kaczmareck, Torsten Teubler, Mohamed Hail|
funded by Innovationsfond Schleswig-Holstein
So called Embedded Systems are devices like mobile phones, mp3-players, DVBT-Receiver, automotive control boxes or ticket machines. Embedded Systems are Computers with CPU, Memory and IO Devices - compared to Personal Computers characteristics like type of constructions, memory size, and IO are tailored to the intended use. Embedded Systems e.g. enable precise diagnostics in medical application, reduce emissions and better stability in curves like ESP and in form of DVBT-Recorder, digital camera and mobile phone are continous companions. Especially within the field of Embedded Systems Germany keeps a leading role due to a competent and large automotive industry.
Wireless Networking of Embedded Systems via RF technologies enable many new application in all areas of life and industry sectors. To implement systems with numerous wireless connected devices new approaches for programming and new protocols are needed that allow a self-organization of devices and achieve the required robustness. Wireless technologies under investigation include WLAN, UWB with high data rates and 802.15.4 and RFID where only a few bits are transferred.
The Lübeck University of Applied Sciences has started a Laboratory to enable practical training on networked Embedded Systems. TriSOS 3xSOS (Smart Object Systems, Self Organizing Systems, Service Oriented Systems) is funded by Innovationsfonds SH.
|||Entwicklung einer kompakten Sensorplattform für prototypischen Einsatz in der Medizintechnik , In ImpulsE (submitted), volume 20, 2015. [bib]|
|||Höhenbestimmung mittels Luftdrucksensoren und differentieller Messung für Indoor-Anwendungen , In ImpulsE, volume 17, 2013. [bib]|
|||Transparent Integration of Non-IP WSN into IP Based Networks , In International Conference on Distributed Computing in Sensor Systems and Workshops IEEE Computer Society, 2012. [bib] [abstract]|
Embedded devices connected to the Internet will start an increasing growth of the Internet in near future. Wireless Sensor Networks (WSN) will play a major role in that growth. In the past several solutions were proposed to make sensor networks IP capable. Today there are IPv6-Stacks available including web servers running on sensor nodes. However, a gateway is always needed to convert the routing protocols and MAC-Layer Protocols including compression of IP packets to run on these devices. The overhead using IPv6 on the nodes is very high in respect of code size and message overhead. Therefore, in our approach we design and implement a system based on simple protocols target for sensor network nodes and a flexible gateway working in a hybrid fashion for our sensor network testbed. We successfully integrated this non-IP WSN in the Internet and our testbed is productive available from any computer connected to the Internet for reference. In this paper we present the architecture of our solution and present the implementation details of a standard WSN application that can be used for evaluation.
|||Cooperative Virtual Memory for Sensor Nodes , Chapter in Real-World Wireless Sensor Networks Springer Berlin / Heidelberg (Pedro Marron, Thiemo Voigt, Peter Corke, Luca Mottola, eds.), volume 6511, 2010. [bib] [pdf] [abstract]|
Wireless sensor networks (WSN) have unique challenges and constraints. Sensor nodes e.g. have tough memory limitations. However, the latest advances in WSN research direct for an implementation of lightweight versions of Internet protocols like IPv6, TCP, and HTTP on sensor nodes. These protocols have challenging requirements. Especially, memory consumption of these protocols is often higher than the physical RAM that microcontrollers have integrated. Therefore, we suggest an approach for virtual memory providing more memory than the available RAM. As microcontrollers do not include a memory management unit the usage of memory is implemented in cooperative fashion based on the C standard library function malloc and free. We suggest an underlying file system and a hardware abstraction layer to support various external or internal memory devices like Flash or EEPROM. In this work in progress we present an API, some implementation details and preliminary results including future work.
|||A Solution for the Naming Problem for Name-Centric Services , In 12th International Conference on Wired & Wireless Internet Communications (WWIC 2014), 2014. [bib] [abstract]|
In recent past name-centric or content-centric networking (CCN) has gained substantial attention in the networking community. In a further development step name-centric service architecture enables the flexible placement and distribution of services in the network especially in a heterogeneous environment of wired and wireless (sensor) networks. However, the problem of structuring and creating hierarchies for names in name-centric networks is not solved yet. E.g. there is no configuration of service names in name-centric service WSN, no concept of unsolicited names or link-local names in CCN. In IP networks, DHCP or IPv6 auto- configuration is available, but no equivalent technique exists for CCN. We analyze the naming problem in the software development life cycle for name-centric services in WSN and propose a structure, hierarchy, and configuration mechanism for names. The paper introduces the overall concept and preliminary steps of implementation.
|||Wiseman - A Management and Deployment Approach for WSN Testbed Software , In 2013 IEEE INFOCOM Student Poster Session (INFOCOM'2013 Student Posters), 2013. [bib] [pdf] [abstract]|
Wireless Sensor Networks (WSNs) are an emerging technology. Today research in this field focuses on WSN testbeds to evaluate algorithms under realistic conditions. Numerous WSN testbed platforms allow remote deployment of WSN code and control of WSN experiments. However, one major aspect for testbeds was not addressed until now, namely the deployment and management of the testbed software itself. By deployment we mean installation and configuration of software. Once deployed on the testbed machines executables or services need maintenance and management. During testbed lifetime, periodic redeployment of testbed software is necessary due to new software versions, configuration changes, or an extension of the testbed. In this work, we present Wiseman a management and deployment approach and an implementation of Wiseman for the Wisebed WSN testbed software.
|||Name-Centric Service Architecture for Cyber-Physical Systems (Short Paper) , In Service-Oriented Computing and Applications (SOCA), 2013 6th IEEE International Conference on, 2013. [bib] [abstract]|
The goal of Service-Oriented Architectures (SOA) is to enable easy cooperation of a large number of computers and orchestration of services that are connected via a network. However, SOA for wireless senor networks (WSN) and cyber-physical systems (CPS) is still a challenging task. Consequently, for design and development of large CPS like WSNs connected to clouds, SOA has not yet evolved as an integral technology. One of the limiting issues is service registration and discovery. In large CPS discovery of services is tedious, mostly due to the fact that services are often semantically bound to a region or an application function while SOA forces service endpoints to be based on addresses of nodes. Also, today, SOA technologies are not used for service composition within sensor nodes and between sensor nodes, and even worse, different methods exist for service access in a WSN and in the backend. Therefore, service development differs largely in WSN and cloud. To overcome this limitation, we suggest a name-centric service architecture for cyber-physical systems. Our architecture is based on (a) using URNs instead of URLs to provide a service-centric architecture instead of service- or location-centric networking, (b) using the well-known CCNx protocol as a basis for our architecture which supports location and access transparency, and (c) employing CCN-WSN as the resource-efficient lightweight implementation for WSNs to build a name-based service bus for CPS. We evaluate the architecture by implementing an example application for facility management.
|||CCN-WSN - a lightweight, flexible Content-Centric Networking Protocol for Wireless Sensor Networks , In 2013 IEEE Eighth International Conference on Intelligent Sensors, Sensor Networks and Information Processing (IEEE ISSNIP 2013), 2013. [bib] [abstract]|
In future Internet research, content centric networking (CCN) is a new promising approach. CCNx has been introduced recently as an open source protocol suite for CCN and implementation base for practical research. In wireless sensor networks (WSNs) research, data or content centric approaches like in-network processing and data aggregation are important. While the principle of CCN is a suitable approach in WSNs, the CCNx protocol suite designed for PCs is not applicable to resource-constrained WSNs. Additionally, gateways necessary between CCNx and WSN are difficult to implement. Therefore, we design, implement and evaluate a lightweight variant of a CCN protocol specifically for WSNs called CCN-WSN. Key concepts of CCNx protocol are integrated but a variety of aspects are revised to meet the memory and computational constraints of sensor nodes and communication patterns in WSNs. E.g. the message format is simplified and some fields are omitted completely. Instead, we propose a flexible naming strategy which extends the functionality of content names to add small amount of data in interest messages. For performance evaluation a challenging time-synchronization application was implemented with CCN-WSN to demonstrate the flexibility of the approach and a comparison with a reference protocol for data dissemination called AutoCast is presented.
|||Short Paper: Collaboration Between VANET Applications Based on Open Standards , In 2013 IEEE Vehicular Networking Conference (VNC) (IEEE VNC 2013), 2013. [bib] [abstract]|
As of today, there is a variety of self-contained vehicular ad hoc network (VANET) applications. In many scenarios, they could complement each other if they would allow for interoperability. However, since they often use different data formats and do not share a common, machine-readable and platform-independent definition of terms and semantics, they cannot mutually understand and reuse each other's data. Consequently, in this paper we propose a VANET Ontology (VO) for defining the semantics of VANET relevant terms and a common VANET Data Representation (VDR) to facilitate interoperability between arbitrary VANET applications.
|||Precise Indoor Altitude Estimation based on differential barometric Sensing for wireless Medical Applications , In Body Sensor Networks Conference 2013 (BSN2013), 2013. [bib] [abstract]|
Some medical applications require precise information of position and orientation of a patient as changes affect pressure condition inside the body. In this paper we focus on altitude estimation, where altitude is a distance, in vertical direction, between a reference and a point of a human body. We suggest equipping wireless sensor nodes with high resolution pressuresensors to calculate the altitude with the barometric formula. We implement a body sensor network based on IEEE 802.15.4 and synchronization mechanism with a reference. Pressure variations due to environmental effects are compensated by cancellation with this differential measurement setup. We demonstrate the need for differential measurements and show with a series of measurements that environmental pressure variations have no significant effect on the proposed altitude estimation. Compared to existing systems, our solution is cost effective, easy to deploy and provides a flexible tradeoff between precision and location lag by adjusting a filter constant.
|||Non-Invasive Cognitive Radio for Firm Real Time Sensor Applications in heterogeneous Radio Environments , In Proceedings of the Sixth International Conference on Sensor Technologies and Applications (SENSORCOMM), 2012. [bib] [pdf] [abstract]|
Some applications in Sensor Networks need firm real-time support in order to work properly. The difference to hard real-time systems is that this type of application can withstand minor violations of the maximum delay and minimum throughput if these violations are limited. Many standards like IEEE 802.15.4 provide standardized means to ensure delay and bandwidth constraints which work well when there are no interferers in the same frequency band. However, in a heterogeneous environment today these approaches fail when the interference is not aware of the IEEE 802.15.4 traffic. Switching the channel is one option to avoid this kind of interference. We suggest a new non-invasive cognitive radio protocol approach where all participants follow simple rules to enable firm real-time conditions in decentralized design. As a demonstrator we use a three-fold pendulum with firm real-time signal delay constraints of 5ms. The contributions of the paper comprise evaluation results by real measurements with the demonstrator system.
|||Efficient Data Aggregation with CCNx in Wireless Sensor Networks , In 19th EUNICE Workshop on Advances in Communication Networking (EUNICE 2013), 2013. [bib] [abstract]|
CCNx is the reference implementation for a content centric networking (CCN) protocol developed by the Palo Alto Research Center CCNx group. It serves also as reference for our CCN-WSN, a CCNx implementation for wireless sensor networks (WSN). Efficient data aggregation with CCN-WSN is a challenge. In order to collect data from source in the network data sinks have to poll data sources with interests and exclude fields in interests are necessary bloating the interest messages. We solve the problem by introducing three building blocks in CCN-WSN: unicast faces for packet filtering and ``link'' abstraction, a forwarding service for creating network overlay structures used by applications and an intra-node protocol providing an API for applications to interact with the forwarding service. For evaluation purpose we implement an application using a forwarding service implementing a tree topology to collect data in the WSN.
|||A Reusable and Extendable Testbed for Implementation and Evaluation of Cooperative Sensing , In The 8th ACM International Workshop on Performance Monitoring, Measurement and Evaluation of Heterogeneous Wireless and Wired Networks PM2HW2N'13, 2013. [bib] [abstract]|
Cooperative sensing has been identi?ed as a potential improvement for cognitive radios to perceive their radio environment. In the past, algorithms have been developed by analysis and simulations exclusively. With cheaper hardware experimental platforms have been used for evaluation purpose recently. Simulations lack realistic propagation models for radio transmission but are reproducible compared to experimental evaluation done by hand. The effects of reduced detection probability and false alarms are not realistic in these simulations. In this paper, we suggest a reusable and extendable automated testbed software and instructions for deployment of own testbeds. Primary users as well as secondary users with cooperating cognitive radios can be flexibly deployed in the testbed within seconds. The advantage is that a series of even long lasting measurements including automatic logging of results can be easily repeated. Results can be assessed on the fly during the ongoing evaluation by accessing debug output remotely. The testbed supports stationary, portable, and in the future mobile radio devices for flexible scenarios as well as monitoring devices for debugging. The testbed and the radio devices are validated by deploying primary and secondary user in a small scenario whose outcome was analyzed beforehand. The results are as predicted and show the usefulness of this approach.
|||Using and Operating Wireless Sensor Network Testbeds with WISEBED , In Proceedings of the 10th IEEE IFIP Annual Mediterranean Ad Hoc Networking Workshop, 2011. [bib] [pdf] [abstract]|
Current surveys and forecast predict that the number of wireless devices is going to increase tremendously. These wireless devices can be computers of all kinds, notebooks, netbooks, Smartphones and sensor nodes that evolve into realworld scenarios forming a "Real-World-Internet" in the future. In our work we focus on the Future Internet with small battery driven devices forming the "Internet of Things". In recent networking research, testbeds gain more and more attention, especially in the context of Future Internet and wireless sensor networks (WSNs). This development stems from the fact that simulations and even emulations are not considered sufficient for the deployment of new technologies as they often lack realism. Experimental research on testbeds is a promising alternative that can help to close the gap. The deployment of testbeds is challenging and user and operator requirements need to be considered carefully. Therefore, the goal is to design an architecture that allows operators of WSN testbeds to offer numerous users access to their testbeds in a standardized flexible way that matches these requirements. In this paper we first identify some of the requirements, then introduce the architecture and general concepts of our WISEBED approach and show how this architecture meets the requirements of both groups. We give an overview of existing WISEBED compatible WSN testbeds that can be used for experimentation today. Main focus in this paper compared to previous work is to address the perspective of both users and operators on how to experiment or respectively operate a WSN testbed based on WISEBED technology.
|||RoombaNet - Testbed for Mobile Networks , In Proceedings of the Workshops der wissenschaftlichen Konferenz Kommunikation in verteilten Systemen 2011 (WowKiVS 2011) Electronic Communications of the EASST (Tiziana Margaria, Julia Padberg, Gabriele Taentzer, eds.), volume 37, 2011. [bib] [abstract]|
The design and deployment of wireless networks needs careful planning including various tools for analysis, simulation and evaluation. Therefore, development of software to support deployment of wireless networks has been subject of intensive research for several years. In particular the evaluation of the influence of mobility remains a challenging task. For deployment of mobile communication networks operators perform simulations and measurements during the planning process with large efforts. In the past the research community based their decisions on development of new protocols on simulations exclusively. While network simulators provide fast investigation of huge and also mobile networks they rely on theoretical models which are often considered as inaccurate and too optimistic. Therefore, more and more real wireless network environments called testbeds are established worldwide most of them with static nodes. Testbeds dedicated towards mobile networks remain a challenge as the effort to build such a network increases with mobility. The work here presents an approach for a fully automated real-world mobile network testbed where nodes are piggybacked on mobile robots. The platform with up to 30 mobile nodes and additional 30 static nodes can emulate various scenarios especially suited for pedestrian scenarios or for slow car movements. In this paper we introduce this testbed which is integrated into the larger Real-World GLab Internet testbed facility. We provide first details of the hardware and software components and provide first evaluations as well as present application examples.
|||Effective Movement Classification for Context Awareness in Medical Applications Networking , In First International Workshop on Medical Applications Networking, 2009. [bib] [abstract]|
Today new medical applications evolve from large stationary devices to small and smart mobile systems that will enable e.g. more efficient post operative health care. These mobile systems that benefit from ongoing miniaturization and energy savings in hardware will allow continuous monitoring of patients accompanying and supporting therapy and detect emergency situations. Additionally to vital data, the physiological load or the context of patients are important to analyze and understand recorded data of mobile patients. Current approaches for movement classification aim to detect very specific movement patterns and are dependent on precise sensor placements and are thus not suited for everyday usage. Therefore, we developed a movement detection and classification algorithm that can be easily integrated in existing embedded devices. Using data from a single accelerometer embedded into the device, the algorithm can classify between different movement patterns -- the ''context'' -- of the monitored person. We will describe the hardware and the algorithm and will provide first evaluation results demonstrating the effectiveness of this approach for providing context awareness in mobile medical applications in real-time.