Transcript Diapositive 1

ns-3 Introduction
Tom Henderson (University of Washington)
July 2014
Modified by Sara Mehar (university of burgundy)
April 2015
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Agenda (ns-3 PART1)
• ns-3 project overview
– Why use ns-3?
– What is ns-3?
– Project organization
• Getting started with ns-3
– Installation
– Examples
• Future directions
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Goal!!
•Learn about the ns-3 project and its goals
•Understand the software architecture,
conventions, and basic usage of ns-3
•Read and modify an example ns-3 script
•Learn how you might extend ns-3 to conduct your
own research
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Why use ns-3?
• to study network performance or protocol
operation in a controllable or scalable
environment
• a tool aligned with the experimentation needs
of modern networking research
• a tool that elevates the technical rigor of
network simulation practice
• Full Oriented Object programming
• Much faster than other simulators
• Support group and mailing list
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Why use ns-3?
• Project provides three annual software releases
• Users interact on mailing lists and using Bugzilla bug
tracker
• Code may be proposed for merge
– Code reviews occur on a Google site
• Maintainers (one for each module) fix or delegate bugs,
participate in reviews
• Project has been conducting annual workshop and
developer meeting around SIMUTools through 2013
– ns-3 Annual Meeting in Atlanta, May 2014
• Google Summer of Code (March-August) five of the past
six summers
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ns-3: An Open Source Network
Simulator
• ns-3 is a discrete-event network simulator
targeted for research and educational use
model developers
Research
ns-3 software
NS-3 Consortium
ns-3 maintainers
Education
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What is ns-3: Discrete event network
simulator
• Model of the evolution of a networked
system through discrete events in time
• Used for experimentation and education
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ns-3 simulation basics
• Simulation time advances in discrete jumps from
event to event
• C++ functions schedule events to occur at
specific simulation times
• A simulation scheduler orders the event
execution
• Simulation::Run() gets it all started
• Simulation stops at specific time or when events
end
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Software overview
• ns-3 is written in C++, with bindings available
for Python
– simulation programs are C++ executables or
Python programs
– ~350,000 lines of C++ (estimate based on cloc
source code analysis)
• ns-3 is a GNU GPLv2-licensed project
• ns-3 is mainly supported for Linux, OS X, and
FreeBSD
• ns-3 is not backwards-compatible with ns-2
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Software overview
The following platforms are lightly supported:
Windows Visual Studio 2012
Windows Cygwin 1.7
Some aspects of ns-3 depend
specifically Linux) support, such as
or TapBridge (link) features,
components are not enabled on
versions cited above.
on Unix (or
the emulation
and those
the Windows
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Software orientation
Key differences from other network
simulators:
1) Command-line, Unix orientation
2) Simulations and models written directly in
C++ and Python
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ns timeline
1990
2000
2010
1988: REAL (Keshav)
regular
releases
1990s: ns-1
1996: ns-2
1997-2000: DARPA VINT
2001-04: DARPA SAMAN, NSF CONSER
2006: NSF CISE CRI Awards
Inputs: yans,
GTNetS, ns-2
ns-3 core development (2006-08)
June 2008: ns-3.1
June 2014: ns-3.20
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Relationship to ns-2
• ns is a discrete-event network simulator for
Internet systems
– protocol design, multiple levels of abstraction
– written in multiple languages (C++/OTcl)
• ns has a companion network animator
called nam
– hence, has been called the nsnam project
ns-3 is a research-oriented, discrete event simulator
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Relationship to ns-2
ns-3 is a new simulator, without backward compatibility
Similarities to ns-2:
• C++ software core
• GNU GPLv2 licensing
• ported ns-2 models: random variables, error models,
OLSR, Calendar Queue scheduler
Differences:
• Python scripting (or C++ programs) replaces OTcl
• most of the core rewritten
• new animators, configuration tools, etc. are in work
• ns-2 is no longer actively maintained/supported
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Software organization
• Two levels of ns-3 software and libraries
1) Several supporting libraries, not system-installed, can be in parallel to ns-3
Netanim
pybindgen
2) ns-3 modules exist
within the ns-3 directory
Click routing
ns-3
module
module
module
module
module
module
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ns-3 Software organization
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ns-3 Software organization
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ns-3 Software organization
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utilities
Current models
devices
bridge
mesh
csma
spectrum
emu
applications
internet
(IPv4/v6)
energy
tap-bridge
protocols
visualizer
aodv
configstore
dsdv
flow-monitor
olsr
netanim
click
stats
mpi
point-topoint
lte
uan
virtualnet-device
mobility
nix-vectorrouting
network
topologyread
propagation
lr-wpan
wifi
wimax
core
openflow
BRITE
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utilities
Current models
devices
bridge
csma
emu
point-topoint
Smart pointers
Dynamic types
Attributes
lte
mesh
Node class
NetDevice ABC
Address types
spectrum
(Ipv4, MAC, etc.)
Queues
Socket ABC
Ipv4 ABCs
Packet sockets
applications
internet
(IPv4/v6)
energy
Packets
Packet Tags
Packet Headers
mpifile writing
Pcap/ascii
tap-bridge
uan
Callbacks
Tracing
Logging
virtualRandom Variables
net-device
protocols
visualizer
aodv
configstore
dsdv
flow-monitor
olsr
netanim
click
stats
mobility
network
nix-vectorEvents
Scheduler
routing
Time arithmetic
topologyread
propagation
lr-wpan
wifi
wimax
core
openflow
BRITE
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Example : AODV protocol
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Example : AODV protocol
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Python bindings
• ns-3 uses a program called PyBindGen to
generate Python bindings for all libraries
v
v
v
Intermediate
Python
program
C++
header
(py)gccxml
PyBindGen
v
C++
bindings
code
Python
module
C++ compiler
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NetAnim
• "NetAnim" by George Riley and John Abraham
– see the 'ns-3share' channel on YouTube
pyviz
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Emulation support
• Support moving between simulation and testbeds or live
systems
• A real-time scheduler, and support for two modes of
emulation
• Linux is only operating system supported
• Must run simulator in real time
– GlobalValue::Bind (“SimulatorImplementationType”,
StringValue (“ns-3::RealTimeSimulatorImpl”));
• Must enable checksum calculations across models
– GlobalValue::Bind (“ChecksumEnabled”, BooleanValue
(true));
• Must sometimes run as root
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ns-3 emulation modes
ns-3 has been designed for integration into
testbed and virtual machine environments.
We have addressed this need by providing two
kinds of net devices:
The first kind, which we call an Emu NetDevice
allows ns-3 simulations to send data on a “real”
network.
The second kind, called a Tap NetDevice allows a
“real” host to participate in an ns-3 simulation as if
it were one of the simulated nodes.
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ns-3 emulation modes
real machine
virtual
machine
ns-3
virtual
machine
ns-3
ns-3
real
machine
real
machine
Testbed
1) ns-3 interconnects real or virtual
machines
2) testbeds interconnect ns-3
stacks
Various hybrids of the above are possible
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Agenda
• ns-3 project overview
– What is ns-3?
– Why use ns-3?
– Relationship to ns-2
• Getting started with ns-3
– Installation
– Examples
• Future directions
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Getting started with ns-3
• Finding what you need
• Contributing to the project
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Resources
Web site:
http://www.nsnam.org
Mailing lists:
https://groups.google.com/forum/#!forum/ns-3-users
http://mailman.isi.edu/mailman/listinfo/ns-developers
Wiki:
http://www.nsnam.org/wiki/
Tutorial:
http://www.nsnam.org/docs/tutorial/tutorial.html
IRC: #ns-3 at freenode.net
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Suggested steps
• Work through the ns-3 tutorial
• Browse the source code and other project
documentation
– manual, model library, Doxygen, wiki
– ns-3 Consortium tutorials (March 2013)
• http://www.nsnam.org/consortium/activities/annual
-meeting-march-2013/
• Ask on ns-3-users mailing list if you still
have questions
– We try to answer most questions
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APIs
• Most of the ns-3 API is documented with
Doxygen
– http://www.stack.nl/~dimitri/doxygen/
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Reading existing code
• Much insight can be gained from reading ns-3
examples and tests, and running them
yourselves
• Many core features of ns-3 are only
demonstrated in the core test suite
(src/core/test)
• Stepping through code with a debugger is
informative
– callbacks and templates make it more challenging
than usual
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FAQs
• Does ns-3 have a Windows version?
– Yes, for Visual Studio 2012
– http://www.nsnam.org/wiki/Ns-3_on_Visual_Studio_2012
• Does ns-3 support Eclipse or other IDEs?
– Instructions have been contributed by users
– http://www.nsnam.org/wiki/HOWTO_configure_Eclipse_with_ns-3
• Is ns-3 provided in Linux or OS X package
systems (e.g. Debian packages)?
– No
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Contributing
• Any amount of help is appreciated!
– Reporting stale documentation to
[email protected]
– Contributing small patches
– Writing new documentation
– Reporting bugs
– Fixing bugs
– Reviewing code of others
– Contributing new code
– Becoming a maintainer
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New project ideas
• Visit the wiki under "Project Ideas" tab
– http://www.nsnam.org/wiki/Project_Ideas
• Students, consider to apply for Google
Summer of Code 2015
– A 10-week summer job that mentors a student
project on ns-3
– Students apply in March 2015 timeframe
– http://www.nsnam.org/wiki/GSOC2014Projects
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Skills requirement
To write a new protocols or modules
C++
Python (plus)
To do analysis and tests
Shell, awk, or Python, ….
Networking basic skills:
IPv4 address utilization, Lan, wifi, …
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Getting started
This section is aimed at getting a user to a
working state starting with a machine that
may never have had ns-3 installed. It covers
Ubuntu platform, prerequisites, ways to obtain
ns-3, ways to build ns-3, and ways to verify
your build and run simple programs.
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Installation (Prerequisites)
Link:
•https://www.nsnam.org/docs/tutorial/html/gettingstarted.html#overview
•https://www.nsnam.org/wiki/Installation
Example for Ubuntu 14.10 release; other
releases or other Debian-based systems may
slightly vary.
C++ (release):
apt-get install gcc g++
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Installation: (Prerequisites)
Python (release):
apt-get install python python-dev
Note: qt4 development tools (Note: qt4, not qt5)
needed for NetAnim animator
apt-get install qt4-dev-tools
…..Other libraries may be required (depends on
the project)
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Installation: ns-3 tarball
$ cd
$ mkdir workspace
$ cd workspace
$ wget http://www.nsnam.org/release/ns-allinone3.22.tar.bz2
$ tar xjf ns-allinone-3.22.tar.bz2
$ ls
bake
constants.py ns-3.22
README
build.py netanim-3.105 pybindgen-0.16.0.886
util.py
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Installation: Building ns-3
$ ./build.py --enable-examples --enable-tests
Waf: Leaving directory `/path/to/workspace/ns-allinone3.22/ns-3.22/build'
'build' finished successfully (6m25.032s)
Modules built:
antenna
aodv
applications
bridge
buildings
config-store
core
csma
csma-layout
….
Modules not built (see ns-3 tutorial for explanation):
brite
click
openflow
Visualizer
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Installation: Building ns-3 with WAF
Configure the optimized code build
$ ./waf clean
$ ./waf --build-profile=optimized --enableexamples --enable-tests configure
Or
Configure the Debug build
$ ./waf clean
$ ./waf --build-profile=debug --enable-examples -enable-tests configure
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Installation: Build
The build system is now configured and you can
build the debug versions of the ns-3 programs by
simply typing
./waf
Testing ns-3
$ ./test.py -c core
92 of 92 tests passed (92 passed, 0 failed, 0
crashed, 0 valgrind errors)
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NS-3 installation video
https://www.youtube.com/watch?v=Fbk89Nb7M0&feature=youtu.be
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Example
Run:
./waf --run hello-simulator
#include "ns3/core-module.h"
using namespace ns3;
NS_LOG_COMPONENT_DEFINE ("HelloSimulator");
int
main (int argc, char *argv[])
{
NS_LOG_UNCOND ("Hello Simulator");
}
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Example
Run:
./waf --run hello-simulator
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Path to examples
/workspaceNS/ns-allinone-3.22/ns3.22/examples/tutorial
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Example2: First.cc
0
Client
1
Server
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Example2: First.cc
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Example2: First.cc
///include
#include "ns3/core-module.h"
#include "ns3/network-module.h"
#include "ns3/internet-module.h"
#include "ns3/point-to-point-module.h"
#include "ns3/applications-module.h"
///ns3 namespace groups all ns-3-related declarations
using namespace ns3;
//declares a logging component called
FirstScriptExample, allows you to enable and disable
console message logging
NS_LOG_COMPONENT_DEFINE ("FirstScriptExample");
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Example2: First.cc
int
main (int argc, char *argv[])
{//time resolution to one nanosecond
Time::SetResolution (Time::NS);
LogComponentEnable
("UdpEchoClientApplication", LOG_LEVEL_INFO);
LogComponentEnable
("UdpEchoServerApplication", LOG_LEVEL_INFO);
///Node creation
NodeContainer nodes;
nodes.Create (2);
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Example2: First.cc
///PointToPoint link
PointToPointHelper pointToPoint;
pointToPoint.SetDeviceAttribute ("DataRate",
StringValue ("5Mbps"));
pointToPoint.SetChannelAttribute ("Delay",
StringValue ("2ms"));
//NetDevice
NetDeviceContainer devices;
devices = pointToPoint.Install (nodes);
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Example2: First.cc
//Internet Stack
InternetStackHelper stack;
stack.Install (nodes);
//Ipv4 network
Ipv4AddressHelper address;
address.SetBase ("10.1.1.0", "255.255.255.0");
Ipv4InterfaceContainer interfaces = address.Assign
(devices);
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Example2: First.cc
//Server UDP application configuration
UdpEchoServerHelper echoServer (9);
ApplicationContainer serverApps = echoServer.Install
(nodes.Get (1));
serverApps.Start (Seconds (1.0));
serverApps.Stop (Seconds (10.0));
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Example2: First.cc
//Client UDP application configuration
UdpEchoClientHelper echoClient
(interfaces.GetAddress (1), 9);
echoClient.SetAttribute ("MaxPackets",
UintegerValue (1));
echoClient.SetAttribute ("Interval", TimeValue
(Seconds (1.0)));
echoClient.SetAttribute ("PacketSize",
UintegerValue (1024));
ApplicationContainer clientApps = echoClient.Install
(nodes.Get (0));
clientApps.Start (Seconds (2.0));
clientApps.Stop (Seconds (10.0));
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Example2: First.cc
//Start and stop the simulation
Simulator::Run ();
Simulator::Destroy ();
return 0;
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Example3: create new module
Path where ns-3 is installed
cd /home/master/1er/1erPhd/tools/tarballs/nsallinone-3.17/ns-3.17/src/
782 ./create-module.py dhvn
Create a new module automatically, for example AAA
./create-module.py AAA
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Agenda
• ns-3 project overview
– What is ns-3?
– Why use ns-3?
– Project organization
• Getting started with ns-3
– Installation
– Example
• Future directions
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Development Priorities
• Software modularity and long-term maintenance
• Improved integration of direct code execution
• Improved integration with container-based and
testbed-based experiment infrastructures
• Simulation-based experiment management
• Usability
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Modularity
• Open source project maintains a (more stable) core
• Models migrate to a more federated development
process
"bake" tool (Lacage
and Camara)
Components:
• build client
• "module store"
server
• module metadata
Figure source: Daniel Camara
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SAFE: Simulation Automation
Framework
• Data collection, transient analysis, management of
independent replications, graphical configuration and
visualization
• In ns-2 realm, similar to projects like ANSWER,
ns2measure, and Akaroa2
Server host
Experiment
execution
manager
Results
database
Simulation
ns-3
client
Simulation
ns-3
client
Simulation
ns-3
Client hosts
client
Figure source: Felipe Perrone
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Usability
• Animation and visualization
PyVis (Carneiro)
NetAnim (Riley and Abraham)
• Linkage to external tools (topology, mobility, statistics)
pyvizhelper APIs
• Improved
NetAnim
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Questions?
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Bibliography
•Tom Henderson (University of Washington), “ ns-3
overview,”
•https://www.nsnam.org/docs/tutorial/html/gettingstarted.html
•https://www.nsnam.org/wiki/Installation
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