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From Synchronized Clocks to Integrable Networks Sensor Network Research at the Austrian Academy of Sciences Thilo Sauter Research Unit for Integrated Sensor Systems Research Unit for Integrated Sensor Systems Status • Start in April 2004 – One of 60 research entities of the Austrian Academy of Sciences – Funded by Austrian National Bank and the province of Lower Austria • 28 researchers in an international team – Austria, Germany, Russia, Pakistan, Italy, Serbia, China • Intensive cooperation with Vienna University of Technology – Technology support • Part of “Technopol” Wiener Neustadt – – – – – Research institutes and companies working in Surface technology Electrochemistry Tribology Microsystems 2 Research Unit for Integrated Sensor Systems Integration – Our Mission • Functional integration – Signal conditioning and processing – Self diagnosis capabilities and adaptability – Sensor fusion • System integration – Horizontal and vertical communication – Distributed sensor networks – Networked embedded systems • Circuit integration – Miniaturization – EMC and energy consumption optimization • Expert integration – Inclusion of all relevant competencies from the beginning on – Co-operation with external partners to complement own technology and application know-how 3 Research Unit for Integrated Sensor Systems Areas of Expertise Circuit Design Sensors • • • Modelling Communication Basis for integrative, system-oriented solutions Focus on system design Open for cooperations 4 Research Unit for Integrated Sensor Systems Operative Approach • Multi-disciplinary combination of traditionally separated know-how areas – – – – – Sensor technology Microelectronics, integrated circuit design Embedded systems Algorithm design, software engineering Network and communication technology • Basis for integrative, system-oriented solutions • Focus on system design – “Closed-loop” (active) sensor principles – Robustness – Transducers, controller structures, and networks optimized for system integration – System modelling and simulation (analytical, numerical) 5 Research Unit for Integrated Sensor Systems Research Focus and Expertise • Resonant and inertial sensors – Viscosity measurement – Magnetic field measurement • Miniaturized thermal sensors – Flow measurement – Thermal conductivity measurement • • Capacitive sensors Smart sensor system architectures – Modular FPGA-based system-on-chip architectures – Signal processing for smart sensors • Clock synchronization in sensor networks – Hard- and software support • • Security aspects Vertical integration 6 Research Unit for Integrated Sensor Systems Clock Synchronization … or how to bring real time into real-time networks… • Goals – Give all distributed nodes in a network a consistent notion of time – Make synchronization as accurate as possible • Applications – – – – – Distributed measurement systems Distributed control systems Reliable data transmission Secure data transmission Network access Master Slave 1 M 2 T T1S Delay Request T S 2 • Approach – Measurement of network delays – Minimization of jitter – Time stamping of data packets on lowest possible layer – IEEE 1588 as common standard T3M Delay Response Master Time 2 T3S T4S Slave Time Research Unit for Integrated Sensor Systems Accuracy • Hardware-assisted time stamping at MAC level – – – – – High-resolution adder-based clock FPGA-based evaluation platforms for NIC and switch 10/100/1000 Base-T support World record: sub-ns synchronization accuracy Implementation in standard µP: HyNet PTP other UDP Jitter IP Sync. Driver Device Driver MAC CSC Switch Fabric MAC MIIS PHY CSC MAC MIIS PHY PHY Research Unit for Integrated Sensor Systems Robustness • Deficiencies of IEEE 1588 – Master is single point of failure – Long switch-over times • New approach: Master Group – – – – Democratic group of nodes Fault tolerant Some nodes with GPS Backup nodes • IEEE1588 Slaves – Synchronized standard compliant – Less traffic between Master Group speaker and slaves (compared to pure democratic approaches) • Part of new version of standard Research Unit for Integrated Sensor Systems Security • No security measures considered in IEEE 1588 – Typical for automation networks… • Security introduces jitter • Ressource limited devices • Handling of intermediate nodes – Switches, transparent clocks – mixed secure and insecure • Approach – – – – – – Vulnerability analysis Definition of parameters Minimum sync cycles Limited set of messages Implementation First published results 13.05.2017 10 Research Unit for Integrated Sensor Systems Methodology • Prototyping – Only reasonable for a few nodes – Cost intensive – Nevertheless needed for proof of concept • Simulation – Large number of nodes can be investigated – High-precision clock synchronization requires adequate (very fine grained) simulation models – Computational expensive Research Unit for Integrated Sensor Systems Position Determination in Wireless Networks • Project running since May 2007 • Goal: find the position of a (unmodified) node in a WLAN network • Applications: Sensor Localization, Security, new Services 13/05/2017 12 Research Unit for Integrated Sensor Systems Method for Localization • Inverse GPS principle – Works with mobile COTS devices • Methodology – Delta measurements – Smart Timing Repeaters are clock synchronized – 3 ns accuracy 13 • FP7 Project FlexWARE – Flexible Wireless Automation in Real-Time Environments • QoS across network borders – Deterministic behavior – Timing guarantees Path A Exte ns om ible d ains Production goods on cart • Scalability Alternate – Dynamic growth Path B – Bandwidth Zone of uncertain connection transparency Coverage Area A Coverage Area B Control Loop – Positioning – Interruption free Wireless temperature sensor J • Flexible paths and roaming Inter a wired ction bet ween - and ( ro wirele ss do aming) main s Research Unit for Integrated Sensor Systems Scalability and QoS in Mixed Wired/Wireless Networks Real Time Backbone Network Valve Controlle 14 • Network Management Position Middleware ÎEEE1451 Interfaces Flex Native I/O Interfaces WARE Communication Middleware Resource Management Communication Protocol Stack* MAC* Physical Layer Technology independent Middleware – Deterministic cyclic exchange due to synchronized timeslots – Seamless roaming and handover – Execution time – Context-aware reaction Application Server A Communication Technology dependencies • Safety and Security Sensors, Actuators, Process Interfaces Virtual Clock Synchronization – Reservation of real-time bandwidth – Access lists – Inter-controller communication – Prescheduled roaming Time Stamping Research Unit for Integrated Sensor Systems Scalability and QoS in Mixed Wired/Wireless Networks 15 Research Unit for Integrated Sensor Systems Integrable Networks – Why? • Interconnection with application - Vertical Integration – Different resource capabilities (energy, execution time,...) – Different notion of “real-time” (layer-specific, just-in-time) – Interconnecting wired and wireless domains – Scalable protocols (network size and platform) n=0 Integrated Sensor n=1 ADC µC Kv NCO n(t) n=8 c ( n s ) 9 • Challenges – – – – – – Low resources of sensor devices Extensibility and scalability Long-time deployment (Security) management Costs Management and configuration 16 d dt Research Unit for Integrated Sensor Systems Flexible Integration • Autonomous software agents – Handling of distributed systems (MES) – Agent system design – Definition and implementation of security strategy • Resource-efficient agent platform for sensor (like) systems ERP ERP ERP Communication via Web Services MES ProductData Data Product Repository Repository OrderAgent Agent Order Supervisor Supervisor Order Order Agent Agent Order Order Agent Agent Order Order Agent Agent Order Order Agent Agent Information Information Collector Collector ResourceAgent Agent Resource Supervisor Supervisor AbilityBroker Broker Ability Communication via ACL Resource Resource Agent Agent Resource Resource Agent Agent Resource Resource Resource Resource 17 Field control Agent Runtime Environment for RFIT Research Unit for Integrated Sensor Systems Framework • Scalable solution • FIPA compliant communication CAgent Behav. 2 Behav. 1 – Advanced message handling – Parallel behavior execution MTS and ACC TCPQueue TCPServer • Highly optimized for resource-limited hardware 200000 ... Behav. n TCPQueue Message Templates Receiver/ Decoder JADE-LEAP TCP- Sender/ Encoder Server FIPA-API X-Board 150000 µs JADE HTTP HTTP HTTP HTTP TCPQueue FIPA-API PC HTTP 100000 FIPA-compliant Agent 50000 0 1 31 61 91 121 151 181 211 241 271 301 331 361 391 18 Research Unit for Integrated Sensor Systems Future Challenges • Scalable communication protocols – Comprehensive protocol family instead of heterogeneous networks – Reduced complexity for network integration • Mixed parallel secure and non-secure systems – Resource optimized security systems • Overall topic: power awareness – Optimized transducers – Improved data processing architectures and algorithms – Communication interfaces and networks • New topic for long-term research: bio-inspired approaches for – Sensors – Data processing – Interfaces and networks 19 Research Unit for Integrated Sensor Systems Thank you for your attention [email protected] 20