TOSSIM Accurate and Scalable Simulation of Entire Tiny

TOSSIM: Accurate and Scalable Simulation of Entire Tiny. OS Application 발표자 : 김 래 영 2004. 8. 19

INTRODUCTION n n Tiny. OS TOSSIM architecture Evaluate TOSSIM’s performance Conclusion

Sensor network simulator n Developing the right simulation tools will be important for sensor network research. n Sensor network simulator key point n Scalability n n Completeness n n Cover as many system interactions as possible Fidelity n n Can handle large networks of thousands of nodes Capture the behavior of the network as a fine grain Bridging n Bridge the gap between algorithm and implementation

Tiny. OS n Tiny. OS is an OS designed for sensor network n n Component-based programming model A set of component

Tiny. OS n Operating system designed for sensor network n n n Component-based programming model Tiny. OS abstracts all hardware resources as components Component have three computational abstraction n Commands n n Events n n Request to a component to perform service Signals the completion of services Tasks n n A function execute Run to completion

TOSSIM : discrete event simulator Compling Tiny. OS component graph discrete event queue Communication services Tiny. OS H/W abstraction components Extensible radio and ADC models

TOSSIM: Compiler Support n Modify the nes. C compiler(ncc) n To support compilation from Tiny. OS component graphs into the simulator framework.

TOSSIM : Execution Model n Interrupts are modeled through simulator events Distinct from Tiny. OS events n Simulator event ->(call) interrupt handler ->(signal) Tiny. OS event n n Tiny. OS task queue n FIFO run to completion model

TOSSIM : Hardware Emulation n Tiny. OS abstracts each hardware resource as a component n TOSSIM emulates the behavior of the underlying raw hardware n n ADC (Analog-to-digital Converter) The Clock

TOSSIM : Radio Models n TOSSIM provides mechanisms to choose the accuracy and complexity of the radio model n TOSSIM has two built-in special case radio-models n n Simple Static

TOSSIM : Communication Services n TOSSIM provides mechanisms n n Allow PC application by communicating with TOSSIM over TCP/IP Tiny. Viz n The TOSSIM visualization tool

TOSSIM : Data Link Layer n The most complex system n n CSMA Single error correction Double error detection Full-packet CRC

TOSSIM : Data Link Layer n Tiny. OS Networking n n Simulation n n AM(Active Message) Tiny. OS networking stack at a bit level 40 kbps for data 20 Kbps for receiving a start symbol 10 Kbps for sending a start symbol

Evaluation n n Fidelity Completeness Bridging scalability

Fidelity : Radio Noise

Fidelity : Packet-level Interactions Factor -Transmission rate -Network density

Completeness : Surge

Completeness : Surge

Bridging n n n TOSSIM compiles directly from Tiny. OS Small number of component replace to emulate Tiny. OS PC toolchain

Scalability n n Using three different application with varying degrees of complexity Simulation is based largely on the amount of communication rather than on the complexity of the application logic itself

DISCUSSION AND FUTURE WORK n n n TOSSIM can provide a scalable, highfidelity simulation TOSSIM can simulate large numbers of moto TOSSIM can replace arbitrary Tiny. OS components

CONCLUSION n TOSSIM n n n Can’t Simulate thread-based systems Maintaining accurate time across motes require a tremendous performance cost. TOSSIM n Scalable, high fidelity simulations of full sessor network application.