Network Simulator(NS2) - Mobile Networking

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Network Simulator(NS2)- Mobile Networking

• 2006. 4. 12
• Sungkyunkwan University UTRI
• 2006710809
• ? ? ?

2
Contents

• What is NS2?
• Installing NS2(linux)
• Study of Fundamental Skill
• Network Component
• Mobile Networking

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What is NS2?

• NS2(Network Simulator version 2)
• Discrete events , Object oriented simulator
• Covers a very large number of application,
  protocol, network types, network elements and
  traffic models
• TCP/IP protocol family - TCP, UDP, FTP, HTTP
• History
• 1989 started as a variant of REAL network
  simulator
• 1995 developed NS1 through VINT project
• 1996 developed NS2
• Now supported by CONSER, NSF, SAMAN, DARPA
• Additional facilities of NS2
• NAM (Network AniMator)
• trace-all
• xgraph

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What is NS2?

• relationship of OTcl and C

• Ex) bind() function
• C s member function
• TcpAgentTcpAgent()
• bind(window_, wind_)
• // bind_time(), bind_bool(), bind_bw()
• OTcl script
• tcp set window_ 200

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What is NS2?

• ns-allinone-2.28 packages directory structure

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What is NS2?

• NS2 objects

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What is NS2?

• List of C Object(NS/ns-2.27/Makefile)

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What is NS2?
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What is NS2?

• relationship of OTcl and C

Principal of NS2 simulator
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What is NS2?

• 1 minute TCL tutorial
• Assigning a value is done through the set
  command
• set a 1
• set b expr a 2
• define the procedure
• proc list_total list
• set tmp 0
• foreach loopVar valueList commandBody
• foreach l list
• incr tmp l
• return tmp
• set c list_total 1 2 3 4 5
• puts "a a b b c c ? result is a1 b3
  c15

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What is NS2?

• 1 minute oTCL tutorial
• Class car
• car instproc init args
• self instvar wheels_ self A pointer to
  object itself
• set wheels_ 4
• Class vw -superclass car
• vw instproc init args
• self instvar wheels_ vendor_
• set vendor_ "vw"
• eval self next args
• set a new car
• puts "A a car with a set wheels_ wheels"
• set b new vw
• puts "B a b set vendor_ with b set wheels_
  wheels"

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Installing NS2(linux)

• Download site
• http//www.isi.edu/nsnam/ns/ns-build.html(NS2 ??
  ????)
• Manual
• http//www.isi.edu/nsnam/ns/doc/index.html
• Tutorial
• http//www.isi.edu/nsnam/ns/tutorial/index.html
• http//osiris.sunderland.ac.uk/ca2stu/netsim/
• NS by Example
• http//csl.changwon.ac.kr/ref_doc/ns2/examples/ind
  ex.html
• Member function of objects
• http//www-sop.inria.fr/planete/software/ns-doc/ns
  -current/HIER.html

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Installing NS2(linux)
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Installing NS2(linux)
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Installing NS2(linux)
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Installing NS2(linux)
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Study of Fundamental Skill

• Construction of the topology
• determining the position of nodes and links
• Writing out a scenario
• Selection of protocols (traffic agents,
  application services)
• Setup a additional variables
• simulation time , etc

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Study of Fundamental Skill
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Study of Fundamental Skill

• An NS simulation starts with the command,set ns
  new Simulator
• generates an NS simulator object instance, and
  assigns it to variable ns (italics is used for
  variables and values in this section). What this
  line does is the following
• Initialize the packet format (ignore this for
  now)
• Create a scheduler (default is calendar
  scheduler)
• List scheduler, Heap scheduler, Calendar
  scheduler
• Select the default address format (ignore this
  for now)
• The "Simulator" object has member functions that
  do the following
• Create objects such as nodes and links (described
  later)
• Connect network component objects created (ex.
  attach-agent)
• Set network component parameters (mostly for
  compound objects)
• Create connections between agents
• (ex. make connection between a "tcp" and "sink")
• Specify NAM display options
• Etc.(ns-2.X/tcl/lib/ns-lib.tcl)

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Study of Fundamental Skill

• In order to have output files with data on the
  simulation or files used for visualization
• we need to create the files using the open
  command
• Trace file
• This member function tells the simulator to
  record simulation traces
• NAM Trace file
• This member function tells the simulator to
  record simulation traces in NAM input format.

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Study of Fundamental Skill

• Termination of the program is done a finish
  procedure
• At the end of ns program we should call the
  procedure and specify at what time the
  termination should occur.
• ns at 125.0 finish
• The simulation can then begin using ns run
• Simple example script

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Study of Fundamental Skill

• set ns new Simulator
• generates an NS simulator object instance, and
  assigns it to variable ns (italics is used for
  variables and values in this section). What this
  line does is the following
• Initialize the packet format (ignore this for
  now)
• Create a scheduler (default is calendar
  scheduler)
• List scheduler, Heap scheduler, Calendar
  scheduler
• Select the default address format (ignore this
  for now)
• The "Simulator" object has member functions that
  do the following
• Create objects such as nodes and links (described
  later)
• Connect network component objects created (ex.
  attach-agent)
• Set network component parameters (mostly for
  compound objects)
• Create connections between agents
• (ex. make connection between a "tcp" and "sink")
• Specify NAM display options
• Etc.(ns-2.X/tcl/lib/ns-lib.tcl)

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Study of Fundamental Skill

• ns color fid color
• is to set color of the packets for a flow
  specified by the flow id (fid).
• ns namtrace-all file-descriptor
• This member function tells the simulator to
  record simulation traces in NAM input format. It
  also gives the file name that the trace will be
  written to later by the command
• ns flush-trace
• Similarly, the member function trace-all is for
  recording the simulation trace in a general
  format.
• proc finish
• is called after this simulation is over by the
  command ns at 5.0 "finish". In this function,
  post-simulation processes are specified.
• set n0 ns node
• The member function node creates a node. A node
  in NS is compound object made of address and port
  classifiers (described in a later section).

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Study of Fundamental Skill

• ns duplex-link node1 node2 bandwidth delay
  queue-type
• creates two simplex links of specified bandwidth
  and delay, and connects the two specified nodes.
• Link source codes "ns-2/tcl/libs/ns-lib.tcl" and
  "ns-2/tcl/libs/ns-link.tcl
• We can insert error modules in a link component
  to simulate a lossy link
• ns queue-limit node1 node2 number
• This line sets the queue limit(size) of the two
  simplex links that connect node1 and node2 to the
  number specified.
• ns duplex-link-op node1 node2 ...
• Give node position (for NAM)

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Study of Fundamental Skill

• set tcp new Agent/TCP
• This line shows how to create a TCP agent.(source
  agent)
• Agents and traffic sources are in fact basic
  objects
• new Agent/TCPSink create a destination agent
• ns attach-agent node agent
• The attach-agent member function attaches an
  agent object created to a node object.
• ns connect agent1 agent2
• After two agents that will communicate with each
  other are created, the next thing is to establish
  a logical network connection between them.

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Study of Fundamental Skill

• ns at time "string
• This member function of a Simulator object makes
  the scheduler to schedule the execution of the
  specified string at given simulation time.

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Study of Fundamental Skill

• The DropTail option
• If the buffer capacity of the output queue is
  exceeded then the last packet to arrive is
  dropped
• Many alternative options exist
• RED ( Random Early Discard)
• FQ (Fair Queueing)
• DRR (Deficit Round Robin)
• SFQ (Stochastic Fair Queueing)
• CBQ (which including a priority and a round-robin
  scheduler)
• TCP is a reliable congestion control protocol
• there are a number variants of the TCP protocol,
  such as Tahoe, Reno, Newreno, Vegas

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Study of Fundamental Skill

• Excute by
• ns filename
• NAM is excuted by a command in the otcl file.
• exec nam out.nam
• raw2xg
• It is command that convert trace file into xgraph
  form.
• raw2xg a out.tr gt out.xg
• Xgraph
• xgraph out.xg or xgraph out?.xg

NAM graphic interface
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Study of Fundamental Skill
Xgraph interface
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Study of Fundamental Skill

• When tracing into an output ascii file, the trace
  is organized in 12 fields as follows
• The meanings of the fields are
• 1. Event It is given by one of four possible
  symbols r,,-,d which correspond respectively to
  receive (at the output of the link), enqueued,
  dequeued, and dropped.
• 2. Time the time at which the event occurs.
• 3. From node the input node of the link at
  which the event occurs.
• 4. To node the output node of the link a which
  the event occurs.
• 5. Pkt type gives the packet type.

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Study of Fundamental Skill

• 6. Pkt size gives the packet size .
• 7. Flags some flags
• 8. Fid This is flow id of IPv6 that a user can
  set for each flow at the input OTcl script.
• 9. Src addr this is the source address in the
  form of node.port.
• 10. dst addr this is the destination address,
  given in the same form .
• 11. Seq num This is the network layer
  protocols packet sequence .
• 12. Pkt id This is the unique id of the packet.

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Mobile Networking

• Contributed from CMUs Monarch project
• (Wireless extension to ns-2)
• Various modules were added to ns-2 to simulate
  node mobility and wireless networking
• Mobile Node
• Ad-hoc Routing(DSR, DSDV, TORA, AODV)
• MAC802.11
• Radio Propagation Model
• Channel

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Mobile Networking

• Agent
• Responsible for packet generations and receptions
• Can think of it as an Application layer
• CBR(Constant Bit Rate), TCP, Sink, FTP, etc.
• RTagent(DSDV, TORA, AODV) or DSR
• Ad-hoc network routing protocols
• Configure multi hop routes for packets
• LL (Link Layer)
• Runs data link protocols
• Fragmentation and reassembly of packet
• Runs Address Resolution Protocol(ARP) to resolve
  IP address to MAC address conversions

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Mobile Networking

• IFq (Interface Queue)
• PriQueue is implemented to give priority to
  routing protocol packets
• Supports filter to remove packets destined to
  specific address
• Mac Layer
• IEEE 802.11 protocol is implemented
• Uses RTS/CTS/DATA/ACK pattern for all unicast
  pkts and DATA for broadcast pkts

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Mobile Networking

• NetIF (Network Interfaces)
• Hardware interface used by mobilenode to access
  the channel
• Simulates signal integrity, collision, tx error
• Mark each transmitted packet with transmission
  power, wavelength etc.
• Radio Propagation Model
• Uses Friss-space attenuation(1/r2) at near
  distance and Two ray ground (1/r4) at far
  distance
• Decides whether the packet can be received by the
  mobilenode with given distance, transmit power
  and wavelength
• Implements Omni Directional Antenna module which
  has unity gain for all direction

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Mobile Networking

• MobileNode ???

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Mobile Networking

• SRNode ???

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Mobile Networking

• Mobile node configuration
• ns_ node-config -addressingType ltusually
  flat or hierarchical used for
• 
  
  wireless topologiesgt
• -adhocRouting ltadhoc routing protocol like
  DSDV, DSR,
• TORA, AODV etcgt
• -llType ltLinkLayergt
• -macType ltMAC type like Mac/802_11gt
• -propType ltPropagation model like
  Propagation/TwoRayGroundgt
• -ifqType ltInterface Queue type like
  Queue/DropTail/PriQueuegt
• -ifqLen ltInterface Queue length like 50gt
• -phyType ltnetwork interface type like
  phy/WirelessPhygt
• -antType ltAnt type like antenna/OmniAntennagt
• -channelType ltChannel type like
  Channel/WirelessChannelgt
• -topoInstance ltthe topography instancegt
• -wiredRouting ltturning wired routing ON or OFFgt

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Mobile Networking

• -mobileIP ltsetting the flag for mobileIP ON or
  OFFgt
• -energyModel ltEnergyModel typegt
• -initialEnergy ltspecified in Joulesgt
• -rxPower ltspecified in Wgt
• -txPower ltspecified in Wgt
• -agentTrace lttracing at agent level turned ON
  or OFFgt
• -routerTrace lttracing at router level turned
  ON or OFFgt
• -macTrace lttracing at mac level turned ON or
  OFFgt
• -movementTrace ltmobilenode movement logging
  turned ON
• or OFFgt

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Mobile Networking

• Options for node configuration

??(Option) Available Value Default
???? ?? ???? ?? ???? ??
addressingType flat ,hierarchical flat
MPLS ON, OFF OFF
?? ? ?? ?? ???? ?? ?? ? ?? ?? ???? ?? ?? ? ?? ?? ???? ??
wiredRouting ON, OFF OFF
llType LL, LL/Sat NULL
macType Mac/802_11, Mac/Csma/Ca, Mac/Sat, Mac/Sat/UnslottedAloha, Mac/Tdma NULL
ifqType Queue/Drop Tail, Queue/DropTail/PriQueue NULL
phyType Phy/WirelessPhy, Phy/Sat NULL
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Mobile Networking
????? ???? ?? ????? ???? ?? ????? ???? ??
adhocRouting DIFFUSION/RATE, DIFFUSION/PROB, DSDV, DSR, FLOODING, OMNIMCAST, AODV, TORA NULL
propType Propagation/TwoRayGround, Propagation/Shadowing NULL
propInstance Propagation/TwoRayGround, Propagation/Shadowing NULL
antType Antenna/OmniAntenna NULL
channel Channel/WirelessChannel, Channel/Sat NULL
topoInstance lttopology filegt NULL
mobileIP ON, OFF OFF
energyModel ON, OFF NULL
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Mobile Networking
????? ???? ?? ????? ???? ?? ????? ???? ??
initialEnergy ltvalue in Joulesgt NULL
rxPower ltvalue in Wgt NULL
txPower ltvalue in Wgt NULL
idlePower ltvalue in Wgt NULL
agentTrace ON, OFF OFF
routerTrace ON, OFF OFF
macTrace ON, OFF OFF
movementTrace ON, OFF OFF
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Mobile Networking
????? ???? ?? ????? ???? ?? ????? ???? ??
errProc UniformErrorProc NULL
toraDebug ON, OFF OFF
???? ???? ?? ???? ???? ?? ???? ???? ??
satNodeType ploar, geo, terminal, geo-repeater NULL
downlinkBW ltbandwidth value, e.g. "2Mb" NULL
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Mobile Networking

• Mobile network simulation

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Mobile Networking

• Sensor network simulation

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• ??? ??? ?????