A Heterogeneous Testbed with TinyOS and EmStar

TinyOS Technology Exchange02/11/05

Martin Lukac – mlukac@cs.ucla.edu

Contributors: Lewis Girod, Thanos Stathopoulos, Nithya Ramanathan, Tom Schoellhammer, Ning Xu, Martin Lukac,

Richard Guy, Deborah Estrin

CENS Systems Lab

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Testbeds for Heterogeneous Applications

• Real applications are heterogeneous– Scaling beyond 40-50 motes is simpler with tiered architecture of

low-power motes and 802.11-enabled microservers

• Heterogeneous systems are still complicated– Separately motes and microservers are complex systems

– 1 binary on one type of platform is hard enough to debug

– Multiple interacting binaries running on several platforms is scary

• We are interested in evaluating and debugging:– Motes operating under real RF conditions

– Interacting motes and microservers

– Coordinated and cooperating microservers

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…

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32863256S3256N

3256

Copy Room

3531

Deborah’s Office

CENS Heterogeneous Testbed

• 39 Nodes – 3rd floor of Boelter Hall

• 26 Mica2s on MIB510s– MDA300’s

• Connected through serial multiplexers to server

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…

…

32863256S3256N

3256

Copy Room

3531

Deborah’s Office

CENS Heterogeneous Testbed

• 13 Stargates with 802.11– Still have Mica2s with

MDA300s

• Connected through wired ethernet

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Centralized SimulationDeployed Radios

• All application code runs on one server• The server uses the real nodes as network interfaces

• Access to all logs• Global view of order of events• Easier measurement

Node 1

Simulation Server

Serial

Wired Ethernet(Sockets)

Node 2 Node 3 Node 4 Node 5 Node 6 Node 7 Node 8

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Node 7

Anatomy of a Node

• EmStar– A Framework for simulation, emulation, and deployment of

heterogeneous sensor networks– Multi-process architecture. Runs on Linux.

• EmTOS– New platform for TinyOS: “make emstar”– Builds a Linux binary from TinyOS code that uses other

EmStar services

• Fusdnet– Remote access protocol for EmStar services

• HostMote– Like serial forwarder: talks to motes over serial– Handles communication between EmTOS and mote

• Transceiver (runs on the mote!)– Transmits and receives packets from hostmote and radio

Serial

Fusdnet

EmTOS

TinyOS App

Transceiver

HostMote

Ethernet

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Centralized SimulationDeployed Radios

…

HostMote

EmTOS

TinyOS App

Simulation Server

EmTOS

TinyOS App

EmTOS

TinyOS App

Fusdnet

…

…

…

HostMote HostMote

Serial Wired Ethernet(Sockets)

Fusdnet

EmStar App EmStar App

Sample command line to start testbed:$ emrun/emsim ../devel/objecttrack/tabs/track.sim

• Collection of tools to script, visualize, and measure running simulation

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Validating Simulation Results

…

HostMote

EmTOS

TinyOS App

Simulation Server

EmTOS

TinyOS App

EmTOS

TinyOS App

Fusdnet

…

…

…

HostMote HostMote

Serial Wired Ethernet(Sockets)

Fusdnet

EmStar App EmStar App

• Radios run in real time – No virtual clock– Can not do precise timing and hardware

interrupts

• Testbed provides “Native” mode– Program motes with TinyOS binary (like Motelab)

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Questions?

Thanks for listening!

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Backup slides are this way

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Mote Emulation

…

HostMote

EmTOS

TinyOS App

Simulation Server

EmTOS

TinyOS App

EmTOS

TinyOS App

motenic motenic motenic

Fusdnet

Serial MUXto Motes

Ethernet Switch

…EmTOS

TinyOS App

EmTOS

TinyOS App

motenic motenic

Stargate

Fusdnet Server

HostMote

Transceiver

Stargate

Fusdnet Server

HostMote

Transceiver

…

Transceiver Transceiver

…

HostMote HostMote Fusdnet

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Microserver & Mote Emulation

Simulation Server

Fusdnet Client

Ethernet Switch…

Stargate

Fusdnet Server

HostMote

Transceiver

…udpd

802.11

Stargate

Fusdnet Server

HostMote

Transceiver

udpd

802.11

EmTOS

TinyOS App

EmStar App

Fusdnet Client

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Hybrid Mode

DbgStub

ESSSink

Multihop

DbgStub

…ESSSink

Multihop

HostMote Serial Protocol

MotesMicroservers

Simulation Server

Serial MUX

Hybrid Mode• Mixture of real and emulated motes• Range of possibilities

EssDse

Transceiver

Transceiver

Transceiver

EssDse

Transceiver

ESSMote

EssDse

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(Runs at scale of emulation array)

EmSim Modes

RealityDeployment

Pure SimulationEmulation Mode

Hybrid Mode

Real Mode

Full Logsand Status

Limited“Out Of Band”

Status Reports

Vis

ibili

ty

No OOB Status

Deployed

Pure Sim

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Testbed Supports Native Mode

• Emulating motes lack reality– Can’t do precise timing and hardware interrupts– Packet timing– Can’t emulate MAC layer

• Testbed provides “Native” mode– Push TinyOS binary to motes (like Motelab)– Can debug over serial line