A Heterogeneous Testbed with TinyOS and EmStar

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A Heterogeneous Testbed with TinyOS and EmStar

• TinyOS Technology Exchange
• 02/11/05
• Martin Lukac mlukac_at_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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CENS Heterogeneous Testbed

• 39 Nodes 3rd floor of Boelter Hall
• 26 Mica2s on MIB510s
• MDA300s
• Connected through serial multiplexers to server

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CENS Heterogeneous Testbed

• 13 Stargates with 802.11
• Still have Mica2s with MDA300s
• Connected through wired ethernet

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Centralized SimulationDeployed Radios
Simulation Server
Node 1
Node 2
Node 3
Node 4
Node 5
Node 6
Node 7
Node 8
Serial
Wired Ethernet (Sockets)

• 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

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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

Node 7
Fusdnet
Ethernet
HostMote
Serial
Transceiver
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Centralized SimulationDeployed Radios
Simulation Server


HostMote
Fusdnet
HostMote
HostMote
Fusdnet
Serial
Wired Ethernet (Sockets)

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

Sample command line to start testbed
emrun/emsim ../devel/objecttrack/tabs/track.sim
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Validating Simulation Results
Simulation Server


HostMote
Fusdnet
HostMote
HostMote
Fusdnet
Serial
Wired Ethernet (Sockets)

• 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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Thanks for listening!

• Questions?

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• Backup slides are this way

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Mote Emulation
Simulation Server


motenic
motenic
motenic
motenic
motenic
HostMote
Fusdnet
HostMote
HostMote
Fusdnet
Serial MUX to Motes
Ethernet Switch
Stargate
Stargate
Fusdnet Server
Fusdnet Server


HostMote
HostMote
Transceiver
Transceiver
Transceiver
Transceiver
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Microserver Mote Emulation
Simulation Server

Ethernet Switch
Fusdnet Client
Fusdnet Client
Stargate
Stargate
Fusdnet Server
Fusdnet Server
HostMote

udpd
HostMote
udpd
802.11
802.11
Transceiver
Transceiver
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Hybrid Mode
Simulation Server
Serial MUX
HostMote Serial Protocol

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

Dbg Stub
Dbg Stub

Motes
Microservers
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EmSim Modes
(Runs at scale of emulation array)
Pure Sim
Deployed
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Testbed Supports Native Mode

• Emulating motes lack reality
• Cant do precise timing and hardware interrupts
• Packet timing
• Cant emulate MAC layer
• Testbed provides Native mode
• Push TinyOS binary to motes (like Motelab)
• Can debug over serial line