1. ASSERT: System Level Wireless Networking Testbed
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ASSERT: System Level Wireless Networking Testbed
Ehsan Nourbakhsh, Jeff Dix, Paul Johnson, Ryan Burchfield, S. Venkatesan, Neeraj Mittal, and Ravi Prakash
Distributed Systems Laboratory
The University of Texas at Dallas

2. Research in wireless networking and distributed systems
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UTD
Research in wireless networking and distributed systems
MAC layer protocols
Autoconfiguration
Routing
Transport layer
MANET/VANET/SensorNets
Algorithm design, simulations, implementation
Before we dive into the design of the testbed it is better to understand WHY we want the testbed. Our research group works in these fields.
LIST
Increasing awareness the simulators for these technologies have there unique simplifying assumptions and differences. (Cavin et al.)
D. Cavin, Y. Sasson, and A. Schiper, “On the Accuracy of MANET
Simulators,” in Proceedings of the Second ACM International Workshop
on Principles of Mobile Computing (POMC), 2002, pp. 38–43
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3. Goals of Wireless Networking Experiments
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Goals of Wireless Networking Experiments
Accuracy
Controllability
Mobility
Repeatability
Cost effectiveness
Data collection
Resource sharing
Multi-nodal capability
Scalability
With those uses in mind our goal was to develop a flexible wireless network testbed with fewer assumptions. We specifically enumerated these goals.
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4. Wireless Experiment Fidelity
Outdoor:
Softball Field
Public Park
Indoor:
EE to CS
CS to EE
Coaxial Testbed:
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5. Testbed: Site Conceptual View
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Testbed: Site Conceptual View
Each site will be a minimal linux device, controlling a unit under test; multiple RF links to neighbors in a “grid”; controlled by a bigger testbed control; controlling attenuators will control the way connections to neighbors is seen by UUT hence a topology is shaped;
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6. Testbed: Site Hardware View
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Testbed: Site Hardware View
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7. Example Interconnection
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8. 11/22/2018
Digital Board
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9. 11/22/2018
RF Board
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10. Assembled Testbed
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11. Testbed Site
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12. Testbed: Software Architecture
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Testbed: Software Architecture
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13. Software Architecture
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Software Architecture
Diagnostics
Test links and sites between experiments.
Update the View of test-bed.
User Interface
Show a GUI to user for designing and initiating experiments.
Web based.
Stateless.
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14. Software Architecture (cont.)
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Software Architecture (cont.)
Topology Mapper
Map the request of user to currently available sites.
Instruct how to change attenuation levels to emulate different scenarios.
Reservation
Reserve available sites for specific experiment.
Inform control center of expired sites.
Handle cancellations.
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15. Software Architecture (cont.)
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Software Architecture (cont.)
Attenuator Control
Set attenuation value on sites
Handle requests to set attenuation values
UUT Control
Communicate with UUT to start and end experiments.
System state is intentionally stale, uses heartbeat messages to update periodically as it goes
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16. Software Architecture (cont.)
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Software Architecture (cont.)
System State
Database of system condition
Sites
Links
Experiments
Logging
Log software messages
Internal to test-bed control
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17. … … … … Experiment Setup Testbed Super-Graph Testbed Super-Graph∞ δ
Testbed Super-Graph …
Experiment Desired Topology … …
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18. Mobility
Base Station
Atten.
UUT/CPE
Atten.
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19. Scalable Architecture No replacement for field-tests Future work
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Conclusion
Platform for:
Repeatable experiments
Mobility experiments
Protocol stress testing
Heterogeneous nodes
Scalable Architecture
No replacement for field-tests
Future work
Multi-path effects
MIMO
Greater range of frequency bands
External users
Information:
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