Transcript Simulators for Sensor Networks

Simulators for Sensor
Networks
Sagnik Bhattacharya
9/12/2001
Overview
• What we need?
• How much effort should we put?
• Simulators :
– JavaSim
– GlomoSim
– NS - 2
– SensorSim
• Comparison
What we want?
• It should perform simulations of our
algorithms. (obviously)
• It should have models for wireless
transmissions and battery models.
• It should be extremely scalable.
• It should be efficient for large simulations.
• There should be technical support.
How much effort should we
put in?
• Build battery and wireless models?
(Preferably no)
• Implement routing?
• How much learning is involved?
• Change basic modules or just add our own
modules?
JavaSim
• Pros
– Very modular
– Easy to use
• Cons
– Geared for wired internetworks
– No wireless support
GlomoSim
• Specific for mobile wireless networks.
• Built as a set of libraries. The libraries are
built in Parsec( a C-based discrete event
simulation language).
• Layered architecture with easy plug-in
capability.
GloMoSim Library
Data Plane
Modular, extensible library for
network models
Model each layer using
abstract or detailed model
Built-in statistics collection at
each layer
Application Processing
Application
RTP Wrapper
TCP, UDP, RSVP
IP
OSPF, AODV, …
Packet Store/Forward
Transport
IP
Network
IEEE 802.11, 802.3, …
Link Layer
MAC Layer
EPLRS, WaveLAN, ...
Radio
Free space, TIREM
Propagation
model
NS - 2
• De facto standard for network
simulations
• Does support wireless simulations
• A primitive energy model is present.
• Lots of documentation.
• Uses Tcl to specify the Components, and
Otcl to glue them together.
NS - 2 (contd.)
• Cons :
– Difficult to use and learn
– Supposedly more useful for getting statistics
for lower level protocols.
– Originally built for wired networks, later
extended for wireless.
– Supposedly, does not work well for large
topologies.
SensorSim
• Extension to NS - 2.
• Provides battery models, radio
propagation models and sensor channel
models.
• Provides a lightweight protocol stack.
• Has support for hybrid simulation.
• To be integrated with NS - 2.
SensorSim Architecture
app
monitor and control
hybrid network
(local or remote)
real sensor apps on
virtual sensor nodes
app
GUI
app
socket
comm
GUI Interface
HS Interface
V
RS232
Ethernet
gateway
V
V
ns
serial
comm
R
V
R
Gateway Machine
modified event scheduler
Simulation Machine
Proxies for real
sensor nodes
Sensor Node Model in SensorSim
Node Function Model
Micro Sensor Node
Applications
Middleware
Network
Protocol Stack
Sensor
Protocol Stack
Network Layer
Sensor Layer
MAC Layer
Physical Layer
Physical Layer
Wireless Channel
Power Model
State
Change
(Energy Consumers and Providers)
Radio Model
CPU Model
Status
Check
Battery
Model
Sensor #1 Model
Sensor #2 Model
Sensor Channel
Power Management Model
BZR event
BZR
event
Transmit
Off
BZR
event
BZR event
Transmit
BZR
event
transmit
Idle
Receive
receive
done
transmit
done
Without Power Management
Off
transmit BZR event Receive
transmit
done
receive
done
Idle
transmit
timeout
Sleep
receive
timeout(3 sec)
With Power Management
SensorSim Problems
• Still at pre-release stage.
• No Documentation.
Comparison
• On paper : SensorSim looks really good.
Their DNS group has already done a lot
of work.
• Effort : GlomoSim seems better.
• Track Record : NS wins. (GlomoSim was
built by UCLA, but still they built
SensorSim)