System Architecture Directions for Networked Sensors Jason Hill, Rober Szewczyk, Alec Woo, Seth hollar, David Culler & Kristofer Pister Presented by Israel Martínez-Arredondo

2 Outline Networked Sensor Characteristics Hardware Organization Tiny Microthreading Operating System (TinyOS) TinyOS Design Components Evaluation

3 Networked Sensor Characteristics Small Physical size and low power consumption Concurrency-intensive Operation Limited Physical Parallelism and Controller Hierarchy Diversity in Desing and Usage Robust Operation

4 Hardware Organization Three sleep modes (idle, power down & power save) Three LEDs to represent outputs Photo-sensor Radio Temperature Sensor Serial Port

5 Tiny Microthreading OS (TinyOS) Requirements (small physical size, modest active power load & tiny inactive load) Two-level scheduling structure High levels of concurrency

6 Tiny OS Design Tiny Scheduler Components Frame Tasks Event Handlers Command Handlers

7 Component Types Hardware Abstractions Synthetic Hardware High Level Software Components 

8 High Level Software Components

9 Putting it All Together

10 Evaluation Small Physical Size Concurrency-Intensive Operations Efficient Modularity Limited Physical Parallelism and Controller Hierarchy Diversity in Usage and Robust Operation

11 Small Physical Size

12 Concurrency-Intensive Operations

13 Efficient Modularity

14 Evaluation (Cont’d) Limited Physical Parallelism and Controller Hierarchy Diversity in Usage and Robust Operation

15 Discussion What are potential avenues for further work and improvements? RFIDs Characteristics Usage Downside

16 References Loren P. Clare, Esther H. Jennings, Jay L. Gao, “Performance Evaluation Modeling of Networked Sensors”, Ca, USA Adrian Perrig, Robert Szewczk, Victor Wen, David Culler, “Security Protocols for Sensor Networks” University of California RFID