网络仿真工具NS的培训文档

1、ns-3 TrainingComputer and Communication Network LabDepartment of Electrical EngineeringNational Sun Yat-Sen University5/13/2013TopicspGetting Started ns-3nWhat is ns-3?nInstallationpA First ns-3 ScriptnTwo tutorial examplespA simple example for this projectnComplete the remaining parts2Getting Start

2、ed ns-3 Please read the following documentsns-3 overview/docs/ns-3-overview.ppt/docs/ns-3-overview.pdfns-3 Tutorial/docs/release/3.13/tutorial/ns-3-tutorial.pdfns-3 Manual/docs/release/3.13/manual/ns-3-manual.pdfWhat is ns-3

3、?pns-3 is a discrete-event network simulator for Internet systemsnns-3 allows researchers to study Internet protocols and large-scale systems in a controlled environmentnns-3 is a new simulator (not backwards-compatible with ns-2)pns-3 is a free, open source software project organized around researc

4、h community development and maintenancenthe target user community is networking researchers and educators4Extensible Software CorepWritten in C+ with optional Python interfacenextensively documented API (doxygen):n/doxygen-release/index.html5Node BasicspAn ns-3 Node is a husk of a

5、 computer to which applications, stacks, and NICs are added6Tracing and StatisticspTracing is a structured form of simulation outputpExample (from ns-2):pProblem: Tracing needs vary widelynwould like to change tracing output without editing the corenwould like to support multiple outputs7ns-3 Has A

6、New Tracing Modelpns-3 solution: decouple trace sources from trace sinkspBenefit: Customizable trace sinks8Downloading ns-3p/nLatest release: ns-3.16 (2012/12/21)9Problems under WindowspCygwin or MinGWpIf you do use Cygwin or MinGW and use Logitech productsnit can cause Cygwin or

7、MinGW DLLs to die in mysterious waypNote that NSC is not supported on OSX or Cygwin.nNetwork Simulation Cradle10Building ns-3 (1/5)11p# ./build.pyBuilding ns-3 (2/5)12p# ./waf -d optimized configurenns-3 uses the waf build systemBuilding ns-3 (3/5)13p# ./waf -d debug configureBuilding ns-3 (4/5)14p#

8、 ./test.py -c coreBuilding ns-3 (5/5)15Running a Script16p./waf -run hello-simulatorBuilding Your Script17p# cp examples/tutorial/first.cc scratch/myfirst.ccp./wafBuilding Your Script18p# ./waf -run scratch/myfirstA First ns-3 Script /ns-allinone-3.10/ns-3.10/examples/tutorialfirst.ccthird.ccBoilerp

9、latepThe first line in the file is an emacs mode line.n pThe ns-3 simulator is licensed using the GNU General Public License.n 20Module IncludespThe code proper starts with a number of include statements.n p././build/debug/ns321Ns3 NamespacepThe next line in the first.cc script is a namespace declar

10、ation.n pLoggingn 22Main FunctionspThe next lines of the script you will find are,n n 23ns3 提供的 log 訊息分成了以下幾個等級：1.NS_LOG_ERROR Log error messages; 2.NS_LOG_WARN Log warning messages; 3.NS_LOG_DEBUG Log relatively rare, ad-hoc debugging messages; 4.NS_LOG_INFO Log informational messages about program

11、 progress; 5.NS_LOG_FUNCTION Log a message describing each function called; 6.NS_LOG_LOGIC Log messages describing logical flow within a function; 7.NS_LOG_ALL Log everything. 8.NS_LOG_UNCOND Log the associated message unconditionally. Topology HelperspCreate the ns-3 Node objects that will represen

12、t the computers in the simulation.n pWe are constructing a point to point linkn 24Topology HelperspWe will need to have a list of all of the NetDevice objects that are createdn 25Internet Stack HelperpProtocol stacks installed on our nodesn pTCP, UDP, IP, etc.pIpv4AddressHelpern n pmake the associat

13、ion between an IP address and a device26ApplicationspTwo specializations of the core ns-3 class Application called nUdpEchoServerApplicationnUdpEchoClientApplicationpUdpEchoServerHelpern 27ApplicationspUdpEchoClientHelpern 28SimulatorpWhat we need to do at this point is to actually run the simulatio

14、n.n pscheduled events in the simulator at 1.0 seconds, 2.0 seconds and two events at 10.0 secondsn 29Building Your ScriptpDrop your script into the scratch directoryn pNow build your first example script using wafn n 30Building Your ScriptpYou can now run the examplen n 31Building a Wireless Network

15、 TopologypAdd the Wifi and the mobility modulesn pThe network topology illustration follows:32Building a Wireless Network TopologypFor enabling or disabling logging components and for changing the number of devices createdn 33Building a Wireless Network TopologypPart of the Wifi networkn pConfigure

16、the PHY and channel helpersn nYet Another Network SimulatorpM. Lacage and T. R. Henderson, “Yet Another Network Simulator,” WNS2 ns-2: The IP Network Simulator, Italy, 2006.phttp:/ a Wireless Network TopologypCreate a channel object and associate it to our PHY layer object managern pNqosWifiMacHelpe

17、r object to set MAC parametersn nrate control algorithmpAARF (Adaptive Auto-Rate Fallback ) algorithm35Building a Wireless Network TopologypThe SSID of the infrastructure networkn pCreate the wifi devices of these stationsn 36Building a Wireless Network TopologypConfigure the AP (access point) noden

18、 pShares the same set of PHY-level Attributes (and channel) as the stationsn 37Building a Wireless Network TopologypSet some Attributes controlling the “position allocator” functionalityn 38The number of objects layed out on a line.Building a Wireless Network TopologypNeed to tell them how to movenR

19、andomWalk2dMobilityModel prandom directionprandom speedn pRectangle (double _xMin, double _xMax, double _yMin, double _yMax)n 39Building a Wireless Network TopologypWant the access point to remain in a fixed position during the simulationn pProtocol stacksn 40Building a Wireless Network Topologypass

20、ign IP addresses to the device interfacesn 41Building a Wireless Network TopologypEnable internetwork routingn n pCreate just enough tracing to cover all three networksn n 42Building a Wireless Network TopologypRun the simulation, clean up and then exit the programn pOutputn 43Read the pcap filesp p 44Plot figuresp p 45An Examp