1. Sensor Network Simulation Simulators and Testbeds Jaehoon Kim Jeeyoung Kim Sungwook Moon

2. Contents 1.Introduction 2.Simulators 1.TOSSIM 2.Avrora 3.Viptos 3.Testbeds 1.MoteLab 2.Kansei 4.Conclusion

3. Introduction  What is a network simulator?  Why a sensor network simulator?  What is a testbed?  Simulators vs Testbeds?

4. Simulators 1.TOSSIM 2.Avrora 3.Viptos

5. TOSSIM  Overview. A TinyOS based interrupt-level discrete event simulator Can capture network behavior at a high fidelity while scaling to thousands of nodes (up to 8192 nodes) Helped to discover bugs in TinyOS Provides a high degree of accuracy by using models of only a few low-level components with or without a few modification of source code

6. TOSSIM  Disadvantages Only compatible with TinyOS No preemption Does not capture CPU time (cycle count) But it would limit scalability. Does not capture energy consumption. It requires adding hooks to the simulator implementations of hardware abstraction components

7. Avrora  Overview A cycle-accurate instruction level sensor network simulator which scales to networks of up to 10,000 nodes Uses a cycle-by-cycle implementation strategy where each node and each device are advanced by one clock cycle every round Performs as much as 20 times faster than its previous simulator(ATEMU) Only 50% slower than TOSSIM

8. Avrora  Disadvantages Did not model clock drift In reality, nodes may run at slightly different clock frequencies over time due to manufacturing tolerances, temperature, and battery reason. Validating timing results with real-world systems for all devices remains as future work Only verified timing results for large programs with radio communication and real hardware for small, simple programs.

9. Viptos  Overview Graphical development and simulation environment for TinyOS-based wireless sensor networks Transforms the diagram into a nesC program Extends the capabilities of TOSSIM to allow simulation of heterogeneous networks Allows application developers to easily transition between high-level simulation of algorithms to low-level implementation and simulation

10. Testbeds 1.MoteLab 2.Kansei

11. MoteLab  Overview Web-based sensor network testbed Set of permanently deployed nodes Web interface for users Direct interaction with individual nodes

12. MoteLab  Details Set of software tools Four main pieces MySQL Database Backend Web Interface DBLogger Job Daemon Use Models Batch Use Real-time Access

13. Kansei  Overview Networked sensing applications at scale Couple general set of arrays Readily add new platforms Addressing the scaling challenge Enables scaling via software in a high fidelity manner

14. Kansei  Details Set of hardware platforms Hardware infrastructure Stationary array Portable array Mobile array Director High fidelity sensor data generation tools Hybrid simulation

15. Conclusion  TOSSIM has good performance but with limited usability  Avrora has slightly improved fidelity but has a 50% slower performance rate (than TOSSIM)  Viptos enables a graphical representation of the simulation on top of TOSSIM  They are different but none are superior or inferior to the other

16. Conclusion (cont’d)  MoteLab provides a web-based interface  Kansei has better scalability  Both provide networked testbeds with shared access for users

17. Any questions?