Introduction to Wireless and Mobile Networking

Transcription

1 Introduction to Wireless and Mobile Networking NS-2 Tutorial-3 Hung-Yu Wei National Taiwan University Speaker: Chih-Yu Wang

2 Wireless/Mobile Simulation Wireless Radio propagation model Other modules: , Mobile Networks: 2 types Mobile Ad Hoc Networks Mobile IP Reference: NS-2 manual Chapter 16 2

3 Simulation Protocol Modules Several traffic source and applications UDP, TCP Mobile IP, Mobile Ad Hoc Routing Protocol , and other wireless access MAC in development Radio Propagation Model, PHY transmission 3

4 Mobile Ad Hoc Networks Routing protocol is the key issue Proactive routing: Destination Sequence Distance Vector (DSDV) Reactive (on-demand) routing Dynamic Source Routing (DSR) Adhoc On-demand Distance Vector (AODV) 4

5 Other Multihop Relay Networks Mobile Ad Hoc Networks Vehicular Ad Hoc Networks Moving faster Wireless Mesh Networks Fixed relay infrastructure End users don t relay Wireless Sensor Networks Sensing (temperature, motion,..etc) + multihop relay networking Energy consumption is critical 5

6 Mobile Node structure

7 Mobile Node Modules Agent Application layer (or Transport layer) modules UDP, TCP, FTP, etc. RTagent DSDV,AODV, DSR, TORA Ad-hoc routing protocol agents 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 7

8 Mobile Node Modules 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 protocol Some other MAC protocols are also available 8

9 Mobile Node Modules 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 Radio signal attenuation Several radio propagation models are supported Check NS-2 manual 9

10 Port Demux Addr Demux Agent (Src/Sink) RTagent (DSDV) Mobile Node Structure - DSDV LL ARP IFq MAC Radio Propagation Model NetIF Channel 10

11 Port Demux Agent (Src/Sink) Mobile Node DSR Structure - DSR LL ARP IFq MAC Radio Propagation Model NetIF Channel 11

12 Example: simple-wireless.tcl

13 Basic NS setting Trace setting Add $ns_ use-newtrace Topology Setting God = General Operations Director 13

14 Configuration Set the variables Load the parameters 14

15 Node Location and Movement No random movement Initial Location Node Moving 15

16 Traffic and basic NS setting TCP traffic Routine before finishing 16

17 Wireless Trace

18 NS-2 Wireless Trace Overview Wireless networking trace NS-2 manual Trace Support Revised format for wireless traces $ns use-newtrace $ns trace-all $tracefd 18

19 Event Wireless Trace s (send), r (receive), d (drop), f (forward) Time t Node property Ni: node id Nx, -Ny, -Nz: node s x,y,z-coordinate Ne: node energy level Nl: trace level, such as AGT, RTR, MAC Nw: reason for the event (why pkt dropping) 19

20 More Wireless Trace Next hop info Hs (source i.e. this node) Hd (destination i.e. next hop node) Packet information at IP level Ix Packet info at MAC level Mx Packet info at "Application level Px See ns-2 manual for details 20

21 Example of wireless trace 21

22 Mobility/Traffic generator

23 Mobility Scenario Generation Reference: ns-2 manual Generation of node-movement and traffic-connection for wireless scenarios /ns-2.xx/indep-utils/cmu-scen-gen/setdest/ Random Waypoint mobility model Randomly generated next destination Pause time Command./setdest v 1 -n <num_of_nodes> -p <pausetime> - M <maxspeed> -t <simtime> -x <maxx> -y <maxy> > <scenario-file> 23

24 Example output of setdest 24

25 Traffic Pattern Generator Randomly generate CBR or TCP traffic pattern Generation of node-movement and trafficconnection for wireless scenarios Might not be updated Check README in the source code directory /ns-2.xx/indep-utils/cmu-scen-gen cbrgen.tcl It generates both CBR and TCP Example ns cbrgen.tcl -type cbr -nn 10 -seed 1 -mc 8 -rate 4.0 ns cbrgen.tcl -type tcp -nn 25 -seed 0 -mc 20 Question? How would you generate mixed CBR and TCP traffic? 25

26 Example output of cbrgen.tcl 26

27 Homework #2 Coming soon (After homework #1 is due) What you will have to do in homework #2 Wireless Network Simulation Compare different routing protocol Different traffic pattern Different mobility pattern 27