Addressing key IoT performance challenges: resource-efficiency, robustness and scalability

Transcription

1 ITU-T Workshop: Internet of Things Trends and Challenges in Standardization Addressing key IoT performance challenges: resource-efficiency, robustness and scalability Christian Wietfeld Geneva, 18 February 2014 Faculty of Electrical Engineering & Information Technology Prof. Dr.-Ing. Christian Wietfeld

2 Content Overview and Introduction Selected on-going IoT-related research: Context-aware Power Consumption Model (CoPoMo) enabling ressource-efficient IoT communication services Communication-aware Potential Fields for robust Wireless networking and Control of Unmanned Aerial Vehicles (Wi-UAV) Interoperable Vehicle2Grid communication ISO/IEC Evaluating scalable Smart Grid communications with hybrid simulation techniques Conclusions Slide 2

3 Who we are Team of 20 full-time researchers and 30 students (70 % third party funded) Research focus: Networking for Cyber Physical Systems / Internet of Things Unique set of experimental equipment: Lab (3G/4G mobile network emulators) Outdoor Testing Site: LTE base station, LTE Sophisticated system simulators and on-going contributions to Open Source projects Contributions to standardization (ISO/IEC 15118, IEC 61850, IETF) Since 2008: 7 Int l Best Paper Awards Award-winning spin-off comnovo Slide 3

4 Introducing a Stochastical Model for Power Consumption Green IoT λ 3 λ 4 Idle P 1 λ 2 Low Power P 2 µ 2 µ 3 High Power P 3 Max. Power P 4 µ 4 λ i depends on the arrival rate of data and the cell environment in terms of the transmission power distribution μ i depends on radio channel dependent throughput and the average file size B. Dusza, C. Ide, L.Cheng and C. Wietfeld, "CoPoMo: A Context-Aware Power Consumption Model for LTE User Equipment", Transactions on Emerging Telecomunication Technologies (ETT), vol. 24(6): , Wiley Slide 4

5 Context Parameters Architecture of the Context Dependent Model Cell Environment File Size Arrival Rate Mobility Trajectory Green IoT System Parameters P Tx,i UE #PRB MCS Center Frequency Empirical Power Consumption Model Throughput Measurements Ray-Tracing CCDF Evaluation R i D λ θ i μ i = R i /D λ i = λ θ i μ i,1 λ 1,i Markovian Model P i P Σ = P i p i i Slide 5

6 Optimizing the battery lifetime of IoT devices: Choosing the right frequency Green IoT Rural Average power consumption [W] 800 MHz Battery life time [h] 2,6 GHz Influence of carrier frequency Enhanced battery lifetime by switching to 800 MHz File Size [Byte] (with 1 File per Minute) B. Dusza, C. Ide, L.Cheng and C. Wietfeld, "CoPoMo: A Context-Aware Power Consumption Model for LTE User Equipment", Transactions on Emerging Telecomunication Technologies (ETT), vol. 24(6): , Wiley Slide 6

7 Optimizing the battery lifetime of IoT devices: Trading local data processing to data offloading Green IoT Rural Average power consumption [W] 800 Battery life time [h] 2, File Size [Byte] (with 1 File per Minute) B. Dusza, C. Ide, L.Cheng and C. Wietfeld, "CoPoMo: A Context-Aware Power Consumption Model for LTE User Equipment", Transactions on Emerging Telecomunication Technologies (ETT), vol. 24(6): , Wiley Slide 7

8 A swarm of aerial IoT devices can achieve more in less time Aerial IoT BUT: control is more complex, as UAVs must cooperate to spread efficiently across the scenario communication within the swarm is key! Slide 8

9 Model-based Development Process Aerial IoT Initial Concept Simulation Validation Refined Control Algorithms & System Concept Software in the Loop Validation Hardware in the Loop Validation Optimized Parameterization Full Experimental Validation Evolved UAV System Desired RSS threshold of -63 dbm Experimental Validation I I RSS measur ement s II Target RSS r eached III SCG D ecrease of distance to maintain desired RSS value -10 db attenuation due to shadowing Shadowing of building SCA1 SCA2 SCA3 II III RSS max RSS min Average RSS Distance between agent s Reduction of tx power by 10 db Holding posit ion Hardware in the Loop Slide 9

10 Example: Communication Aware Potential Fields (CAPF) Aerial IoT Potential Fields impose attracting/repelling forces on UAVs based on RSSI measurements The total force on each UAV is defined as: p a F i = F OOOO j=1 + F RRR + F Aii j=1 + F CCC p total number of repelling forces F OOOO Repelling force of obstacle j to UAV i a total number of attracting or repelling UAVs F RRR Repelling force of UAV j to UAV i (coverage) F Aii Attracting force of UAV j to UAV i (comm.) F CCi Attracting force of moving team to UAV i Slide 10

11 System goodput stable despite changing channel conditions Aerial IoT Robustness check through protocol simulation: Metric: Goodput Protocol Simulation for transmitting telemetry data between UAVs: 250 kbit/s data stream between 5 UAVs (each-2-each) Goodput stays constant due to reduced inter-uav distances Proposed algorithms are robust and scale Slide 11

12 ICT-Architecture for Automation and Network Integration Electric Vehicles Backend Mobility Services Electric Vehicle Electric Vehicle Electric Vehicle Services Safety Backend Utility Back-End Network Services Electric Vehicles Charging Infrastructure Back-End Infrastructure Front-End Communication Vehicle to Grid(V2G) Back-End Communication Slide 12

13 Organization of ISO/IEC Joint Working Group Electric Vehicles ISO TC22 / SC3 Convener ISO/IEC V2G CI Joint Working Group IEC TC 69 Convener Layer 5-7 Project Team 1: Use Cases Project Team 2: Messages, Sequences & Timings Project Team 5: Security Project Team 6: Conformance Testing Layer 3+4 Project Team 3: Intermediate OSI Layers Layer 1+2 Project Team 4: Wired PHY + MAC ISO/IEC Part 1 General Information & Use Case Definition ISO/IEC Part 2 Technical Protocol Description & OSI-Layer Requirements ISO/IEC Part 3 Physical Layer & Data Link Layer Req. ISO/IEC Conformance Tests Part 4 Network and application protocol Part 5 Physical and Data Link Layer Slide 13

14 Organization der ISO/IEC Joint Working Group Electric Vehicles ISO TC22 / SC3 Convener ISO/IEC V2G CI Joint Working Group IEC TC 69 Convener Layer 5-7 Project Team 1: Use Cases Project Team 2: Messages, Sequences & Timings Project Team 5: Security Project Team 6: Conformance Testing Layer 3+4 Project Team 3: Intermediate OSI Layers Layer 1+2 Project Team 4: Wired PHY + MAC OEMs Utilities / System Operators Infrastructure / Component Suppliers & Service Providers Slide 14

15 ICT-Standards for interoperable charging processes Electric Vehicles Example contribution Optimization of the communication protocols based on most recent Web Services standards (Embedded Web Services) XML schema informed EXI strict byte pkd EXI strict bit pkd Reduction by 95% Contributions to open reference implementation Open V2G Prototype implementation of ISO/IEC CNI V2G-Simulator for validation of fully automated V2G-Communication Schmutzler, J. and Wietfeld, C., "Analysis of Message Sequences and Encoding Efficiency for Electric Vehicle to Grid Interconnections", IEEE Vehicular Networking Conference (VNC) 2010, Jersey City, New Jersey, USA, IEEE, pages: , Dec Slide 15

16 Hybrid Simulator INSPIRE: Integrated Co-Simulation of Power and ICT Systems for Real-Time Evaluation Simulation Core: Master event and time control Generic network description Networking Layer: Connectivity between simulators Using the High Level Architecture (IEEE ) Management Layer: Main configuration Database Event logging Scenario configuration Statistical analysis Incident generation Power system simulator Power plant simulator Main configuration Scenario configuration Generic network description Networking layer Simulation core Database Statistical analysis Management layer Master event and time control Eventlogging Incident generation ICT simulator Algorithms for protection and control technology Legend: simulator specific network connection e.g. Web Services, Sockets, etc. Smart Grid H. Georg, S. C. Müller, C. Rehtanz and C. Wietfeld, "A HLA Based Simulator Architecture for Co-simulating ICT Based Power System Control and Protection Systems", 3rd IEEE International Conference on Smart Grid Communications (SmartGridComm 2012), Tainan City, Taiwan, Nov 2012 awarded with a Best Paper Award Slide 16

17 Conclusions Internet of Things is a hot topic in on-going research (naming varies, cf. Cyber Physical Systems, etc.) Key challenges are: Resource-efficiency (spectrum, but also energy) Robustness (even in harshest environments) Scalability (even for continent-wide Smart Grids) Standards are essential to ensure IoT interoperability: New protocols are developed in area-specific standardization groups (e.g. energy, automotive) Research institutes can help to enable cross-innovation to leverage most recent ICT state-of-the-art in on-going standardization projects Slide 17