Study of MANET Routing Protocols by Simulation Experiments by fxp16739

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									Study of MANET Routing Protocols
   by Simulation Experiments


  As Partial Requirement of CIS 595 Master’s Project
             Ashwini Kumar Pandey
        Department of Computer Science
     Southern Illinois University Edwardsville
                     MAY 2004
Introduction


           Wireless Networks

   With Infrastructure   Without Infrastructure




                                                  2
Introduction


           Wireless Networks
       With Infrastructure   Without Infrastructure




                                                      3
Introduction



           Wireless Networks
     With Infrastructure   Without Infrastructure




                                                    4
Introduction

Challenges with Mobile Ad
   hoc Network (MANET)
 No Central Controlling
   Authority
 Limited Power
   availability


A lot of work is currently
going on in different
areas to overcome the
challenges faced with
MANETs

                             5
Categorization Of Ad hoc Routing Protocols



                         Ad hoc Routing Protocols




         Proactive Protocols                      Reactive Protocols



                               Hybrid Protocols




 DSDV   WRP      FSR                ZRP           AODV     DSR         ABR




                                                                             6
Distance Vector Routing Protocol

 Table based protocol.
 Consists of distance tables (or “vectors”) of least cost
  path to all the other nodes in a network.
 Susceptible to routing loops




                                                             7
Wireless Routing Protocol (WRP)

   Table based protocol.
   Consists of :
            Distance table
            Routing table
            Link-cost table
            Message retransmission list (MRL) table
   Each node sends periodic update messages (“hello” or
    new information)
   Avoids routing loops by checking the status of direct link
    of all the immediate neighbor each time any update is
    done



                                                             8
Dynamic Source Routing (DSR)
Consists of Two Phases:
     -Route Discovery : Start with checking route
  cache. Then start RRP with a unique identifier

                                             Route Request
                                          N1-N2                 N1-N2-N5
                                 N2                                                 Destination
                                                       N5
                       N1                                                   N8


                                                                                 N1-N3-N4-N7
         Source   N1                                     N1-N3-N4


                                                                           N7
                   N1
                                                  N4
                                                                N1-N3-N4
                            N3
                                  N1-N3                                    N1-N3-N4-N6
                                                                     N6
                                                  N1-N3-N4




                                                                                               9
Dynamic Source Routing (DSR)

Consists of Two Phases:
      -Route Discovery
                                                      Route reply

                               N1-N2-N5-N8
                                                  N1-N2-N5-N8
                          N2                                          Destination
                                             N5
       N1-N2-N5-N8                                               N8



    Source N1

                                                                N7
                                    N4

                     N3
                                                       N6




                                                                                    10
Dynamic Source Routing (DSR)

Consists of Two Phases:
         -Route Discovery
         -Route Maintenance : accomplished through use of error
    packets.
Advantages:
-Source Routing (routing information in source node only)
-Routes created on demand
-Use of route cache
-Presence of multiple routes
-No periodic checking of routes
Disadvantages:
-Initial delay in transmission, may not be acceptable in certain
    situations
-Longer paths possible
-May not be suitable for large networks.
                                                          11
Ad hoc On Demand Distance Vector Routing
Protocol (AODV)

 Routes are created on demand but maintained in
  tables
 Only the routing information for the routes
  currently in use is maintained in tables
 Routing process consists of two steps:
     -Route discovery
     -Route maintenance




                                                   12
                                                            RREQ Packet Propagation


Route Discovery                                     N2
                                                                     N5
                                                                                                     Destination
                                                                                               N8

Each node maintains:
                         Source N1
-Route table
                                                                                           N7
-Broadcast ID: incremented for                                 N4
each new RRP
                                          N3
                                                                                 N6
-Node sequence number
RRP is broadcast to immediate
neighbor only
                                                         Route Reply Packet Propagation


Route Maintenance                              N2
                                                                N5
                                                                                                    Destination
                                                                                          N8
-error message
-hello message         Source N1
                                                                                      N7
-route time-out
                                                          N4

                                     N3
                                                                            N6
AODV Protocol

      Advantages:
      -control overhead will be less as compared to
         purely table based protocols as routes are
         created only on demand
      -routes are guaranteed to be loop-free and
         valid
      -well suited for large networks

      Disadvantages:
      -requirement of symmetric routes
      -use of periodic hello messages


                                                      14
Experiment Modeling

 The performance of protocols was compared based on
  the following three metrics:
  - End-to-end delay: the average time between a packet
  transmission at source node until packet delivery to a
  destination
  -Reliability: the ratio of packets successfully delivered to
  the total number of packets sent
  -Routing overhead: the number of control packets
  generated by each routing protocol
 The control parameters are:
  -Traffic Load
  -Node Mobility
  -Node Density

                                                             15
Experiment Modeling (contd.)

   Traffic load is modeled using constant bit rate data stream with the
    following three loads:
         (i) Low Traffic Load: A packet is sent every 10 second
         (ii) Medium Traffic Load: A packet is sent every second
         (iii) High Traffic Load: A packet is sent every 0.1 second
   Movement of nodes is modeled using the “random waypoint
    model”
   Terrain size is fixed at 2000 X 2000 m
   Radio range is 175 m
   Bandwidth of each link is 2 Mbps
   The simulation time is 500 seconds for all cases
   TCP is NOT used in transport layer as it performs flow control and
    retransmission whereas our aim is to study the protocols
   Before the start of actual simulation random traffic is generated
   The simulator used was Glomosim.

                                                                     16
Experiment Design

Following two experiments were performed:
For both experiments 25 nodes act as senders and another 25 act
 as receivers, working almost simultaneously.


Experiment #1 (Mobility Test): Study the effect of node
mobility.
50 nodes moving according to random waypoint model at a fixed
speed of 20 m/s (72 km/h) with following five levels of node
mobility:
   (i) Perpetual Mobility (Pause time 0 sec)
   (ii) High Mobility (Pause time 120 sec)
   (iii) Medium Mobility (Pause time 300 sec)
   (iv) Low Mobility (Pause time 400 sec)
   (v) Zero Mobility (Pause time 500 sec)
                                                          17
Experiment Design

Experiment #2 (Node Density Test): Study the effect of
change in node density on the performance metrics for
different protocols.
Nodes are moving continuously at 20 m/s, with the following
three levels:
    (i) Low Density Network: 50 nodes in the network
    (ii) Medium Density Network: 75 nodes in the network
    (iii) High Density Network: 100 nodes in the network




                                                         18
Results
                                                                                                   Medium Traffic Load
Experiment #1
                                                                                                                       3500

                                                                                                                       3000




                                                                                        Number of Control Packets
Control Overhead for
                                                                                                                       2500
                                                                                                                                                                               AODV
                                                                                                                       2000

different mobility levels
                                                                                                                                                                               DV
                                                                                                                                                                               DSR
                                                                                                                       1500
                                                                                                                                                                               WRP
                                                                                                                       1000

                                                                                                                       500

                                                                                                                         0
                                                                                                                              0       100     200         300      400   500
                                                                                                                                            Pause Time (seconds)




    Low Traffic Load                                                                               High Traffic Load
                             3500                                                                                      12000

                             3000
                                                                                                                       10000



                                                                                           Number of Control Packets
 Number of Control Packets




                             2500
                                                                                                                        8000
                                                                                 AODV                                                                                          AODV
                             2000
                                                                                 DV                                                                                            DV
                                                                                                                        6000
                             1500                                                DSR                                                                                           DSR
                                                                                 WRP                                    4000                                                   WRP
                             1000

                             500                                                                                        2000

                               0                                                                                              0
                                    0   100     200         300      400   500                                                    0   100     200         300      400   500
                                              Pause Time (seconds)                                                                          Pause time (seconds)




                                                                                                                                                                                      19
Results
                                                                                       Medium Traffic Load
Experiment #1                                                                                                                                    100




                                                                                                                  Packet Delivery Rate (%)
                                                                                                                                                 80

Packet Delivery Rate for                                                                                                                         60
                                                                                                                                                                                                        AODV
                                                                                                                                                                                                        DV

different mobility levels                                                                                                                        40
                                                                                                                                                                                                        DSR
                                                                                                                                                                                                        WRP


                                                                                                                                                 20


                                                                                                                                                  0
                                                                                                                                                       0    100      200        300      400    500
                                                                                                                                                                  Pause Time (seconds)




 Low Traffic Load                                                                      High Traffic Load
                             100                                                                                              30


                             80                                                                                               25
  Packet Delivery Rate (%)




                                                                                       Packet Delivery Rate (%)
                                                                                AODV                                          20
                             60                                                                                                                                                                          AODV
                                                                                DV
                                                                                                                              15                                                                         DV
                                                                                DSR
                             40                                                                                                                                                                          DSR
                                                                                WRP
                                                                                                                              10                                                                         WRP
                             20
                                                                                                                                             5

                              0                                                                                                              0
                                   0   100     200         300      400   500                                                                    0         100      200         300       400     500
                                             Pause Time (seconds)                                                                                                 Pause Time (seconds)




                                                                                                                                                                                                                20
Results
                                                                                             Medium Traffic Load
Experiment #1                                                                                                                                2.4




                                                                                                           Mean end-to-end delay (seconds)
Mean End-to-end delay for
                                                                                                                                             2.0

                                                                                                                                             1.6

different mobility levels
                                                                                                                                                                                                  AODV
                                                                                                                                                                                                  DV
                                                                                                                                             1.2
                                                                                                                                                                                                  DSR
                                                                                                                                             0.8                                                  WRP


                                                                                                                                             0.4

                                                                                                                                             0.0
                                                                                                                                                   0   100     200         300       400   500
                                                                                                                                                             Pause Time (seconds)




 Low Traffic Load                                                                            High Traffic Load
                                   3.5                                                                                                       35




                                                                                             Mean end-to-end delay (seconds)
 Mean end-to-end delay (seconds)




                                   3.0                                                                                                       30

                                   2.5                                                                                                       25

                                                                                      AODV                                                                                                        AODV
                                   2.0                                                                                                       20
                                                                                      DV                                                                                                          DV
                                   1.5                                                DSR                                                    15                                                   DSR
                                                                                      WRP                                                                                                         WRP
                                   1.0                                                                                                       10

                                   0.5                                                                                                        5

                                   0.0                                                                                                        0
                                         0   100    200         300       400   500                                                                0   100     200          300      400    500

                                                   Pause Time (seconds)                                                                                       Pause Time (seconds)




                                                                                                                                                                                                         21
                                      Analysis




                                                                                                                               Relative Increase in packet delivery rate
                                      600%                                                                                                                                 800%
  Increase rate in routing overhead




                                                                                                                                                                           700%
                                      500%
                                                                                                                                                                           600%
                                      400%                                                         DV                                                                                                                   DV
                                                                                                                                                                           500%
                                                                                                   AODV                                                                                                                 AODV
                                      300%                                                                                                                                 400%
                                                                                                   DSR                                                                                                                  DSR
                                                                                                                                                                           300%
                                      200%                                                         WRP                                                                                                                  WRP
                                                                                                                                                                           200%
                                      100%
                                                                                                                                                                           100%
                                       0%                                                                                                                                   0%
                                             Low    Medium       High                                                                                                                Low           Medium        High
                                                   Trffic Load
                                                                                                                                                                                                  Traffic Load

The ratio of the control packets at perpetual                                                                           The relative increase in packet delivery rate
mobility to that of zero mobility in percent                                                                            when mobility is decreased to zero mobility
                                                                                                800%
                                                                        Mean End-to-end Delay
                                                                         Relative Increase in




                                                                                                600%
                                                                                                                                                                                           DV
                                                                                                                                                                                           AODV
                                                                                                400%
                                                                                                                                                                                           DSR
                                                                                                                                                                                           WRP
                                                                                                200%


                                                                                                 0%
                                                                                                          Low    Medium                                                       High
                                                                                                                Traffic Load


                                                                 The ratio of mean end-to-end delay at perpetual
                                                                 mobility to that of zero mobility
                                                                                                                                                                                                                              22
Results
                                                                                         Medium Traffic Load
Experiment #2                                                                                                          5000




                                                                                         Number of Control Packets
                                                                                                                       4000

Control overhead for                                                                                                   3000
                                                                                                                                                                                 DV

different node densities
                                                                                                                                                                                 AODV
                                                                                                                                                                                 DSR
                                                                                                                       2000
                                                                                                                                                                                 WRP

                                                                                                                       1000


                                                                                                                         0
                                                                                                                                  100                   75                  50
                                                                                                                                         Node Density (nodes per network)



 Low Traffic Load                                                                        High Traffic Load
                             5000                                                                                      14000

                                                                                                                       12000
 Number of Control Packets




                                                                                           Number of Control Packets
                             4000
                                                                                                                       10000
                                                                                  DV                                                                                             DV
                             3000                                                                                       8000
                                                                                  AODV                                                                                           AODV
                                                                                  DSR                                   6000                                                     DSR
                             2000
                                                                                  WRP                                                                                            WRP
                                                                                                                        4000
                             1000
                                                                                                                        2000

                               0                                                                                              0
                                    100                  75                  50                                                    100                  75                  50
                                          Node Density (nodes per network)                                                                Node Density (node per network)



                                                                                                                                                                                        23
Results
                                                                                       Medium Traffic Load
Experiment #2
                                                                                                                             30

                                                                                                                             25




                                                                                       Packet Delivery Rate (%)
Packet delivery rates for                                                                                                    20                                                                  DV
                                                                                                                                                                                                 AODV

different node densities
                                                                                                                             15
                                                                                                                                                                                                 DSR
                                                                                                                             10                                                                  WRP

                                                                                                                                        5

                                                                                                                                        0
                                                                                                                                                100                   75                   50
                                                                                                                                                       Node Density (nodes per network)




 Low Traffic Load                                                                      High Traffic Load
                             30                                                                                                         20
                                                                                                                                        18
                             25




                                                                                                             Packet Delivery Rate (%)
                                                                                                                                        16
  Packet Delivery Rate (%)




                                                                                                                                        14
                             20                                                 DV                                                                                                               DV
                                                                                                                                        12
                                                                                AODV                                                                                                             AODV
                             15                                                                                                         10
                                                                                DSR                                                                                                              DSR
                                                                                                                                            8
                             10                                                 WRP                                                                                                              WRP
                                                                                                                                            6

                             5                                                                                                              4
                                                                                                                                            2
                             0                                                                                                              0
                                  100                  75                  50                                                                    100                   75                   50
                                        Node Density (nodes per network)                                                                                Node Density (nodes per network)



                                                                                                                                                                                                        24
  Results
                                                                                             Medium Traffic Load
                              Experiment #2
                                                                                                                                                 0.6




                                                                                              Mean end-to-end delay (seconds)
                                                                                                                                                 0.5


                              Mean end-to-end delay for                                                                                          0.4                                                                   DV
                                                                                                                                                                                                                       AODV

                              different node densities
                                                                                                                                                 0.3
                                                                                                                                                                                                                       DSR
                                                                                                                                                 0.2                                                                   WRP

                                                                                                                                                 0.1

                                                                                                                                                       0
                                                                                                                                                              100                   75                       50
                                                                                                                                                                     Node Density (nodes per network)



Low Traffic Load                                                                             High Traffic Load
Mean end-to-end delay (seconds)




                                  2.0                                                                                                                  12.0




                                                                                                                     Mean end-to-end delay (seconds)
                                                                                                                                                       10.0
                                  1.6
                                                                                      DV                                                                8.0                                                       DV
                                  1.2                                                 AODV                                                                                                                        AODV
                                                                                                                                                        6.0
                                  0.8                                                 DSR                                                                                                                         DSR
                                                                                      WRP                                                               4.0                                                       WRP
                                  0.4
                                                                                                                                                        2.0
                                  0.0
                                                                                                                                                        0.0
                                        100                 75                   50
                                                                                                                                                               100                 75                   50
                                              Node Density (nodes per network)                                                                                       Node Density (nodes per network)



                                                                                                                                                                                                                       25
       Analysis
                                          400%                                                                                                                                 250%
   Relative increase in control packets




                                                                                                                                            Increase in Packet Delivery Rate
                                                                                                                                                                               200%
                                          300%
                                                                                                                     DV                                                                                                         DV
                                                                                                                                                                               150%
                                                                                                                     AODV                                                                                                       AODV
                                          200%
                                                                                                                     DSR                                                                                                        DSR
                                                                                                                                                                               100%
                                                                                                                     WRP                                                                                                        WRP
                                          100%
                                                                                                                                                                               50%


                                           0%                                                                                                                                   0%
                                                 Low    Medium            High                                                                                                               Low           Medium        High
                                                       Traffic Load                                                                                                                                       Traffic Load


The ratio of the number of control packets                                                                                           The ratio of the packet delivery rate observed at
observed at high node density to that                                                                                                high node density to that observed at low node
observed at low node density                                                                                                         density
                                                                                                              250%
                                                                           Increase in Packet Delivery Rate




                                                                                                              200%

                                                                                                                                                                                                   DV
                                                                                                              150%
                                                                                                                                                                                                   AODV
                                                                                                                                                                                                   DSR
                                                                                                              100%
                                                                                                                                                                                                   WRP
                                                                                                              50%


                                                                                                               0%
                                                                                                                       Low    Medium                                                  High
                                                                                                                             Traffic Load


                                                                      The ratio of the mean end-to-end delay observed at low
                                                                      node density to that observed at high node density                                                                                                               26
Conclusions

 DSR has least overhead overall and is least
  vulnerable to node mobility in terms of routing
  overhead.
 Distance vector performed better than our
  expectation in some situations.
 Proactive protocols are less vulnerable to increase
  in traffic load than reactive protocols.
 Packet delivery rate is low for all the protocols
  when the mobility is perpetual.
 At all traffic loads DSR has the longest delay and
  WRP has the shortest delay.

                                                        27
Conclusions

 One of the advantages in using the protocols
  designed for MANETs is their scalability wrt control
  overhead when node density changes. For DV
  protocol, the control overhead increase is much too
  high when node density changes from low to high.
 WRP is the best protocol if high reliability is desired.
 DV protocol has the worst scalability wrt end-to-
  end delay when node mobility increases. This
  implies that one of the primary advantages in the
  three protocols specially designed for MANETs is
  the scalability of these for delay when mobility
  increases.
                                                        28
Future Work

 Measure the actual number of bytes
  sent for control messages (instead of
  measuring the number of packets).

 Perform simulation for different node
  movement speeds.



                                          29

								
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