Ad-hoc Networks by nazef

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									Ad-hoc Networks


  Farouk Kamoun
  Esprit
  Module d'ouverture
  2009-2010
    WLan Wi-Fi Alliance
   Wi-Fi Alliance : Organization that groups the major
    wireless market players in the world
   Its Objective:
     promote Wi-Fi as an international standard for wireless
       networks
     Garantee interoperability of Wi-Fi (Wireless Fidelity)
       products
     Garantee security in Wi-Fi (WPA & WPA2)

     Garantee QoS (Wi-Fi MultiMedia)




                           Self-Defending Software         2
   Wlan infrastructure mode (ESS)
                                                                                                               Internet

                                                         distribution Systèm




                                                                                                           Main
                                                                                                      Charactéristics :
                                                                                                         • Network ID
                                                                           Point d’accès
                    Point d’accès
                                                                                                            (SSID)
                                                    STATION


STATION
                                                                                           STATION   • Transmission Canal
                                    STATION




          STATION
                                                                 STATION
                                                                                                          • Security
                                                                            BSS                          Mechanisms
                     BSS
                                                                                                          • Topology
                                              ESS


                                                          Self-Defending Software                                       3
Channel Access:CSMA/CA
 Instead of Collision Detection we look for:
 Collision Avoidance (CA)
 CSMA/CA is based on :
   Listening the channel
       Physical Carrier Sense
       Virtual Carrier Sense
           Reservation Mechanism (RTS/CTS)
           Network Allocation Vector (NAV)

   Timers IFS
   Backoff algorithm
   Positive Acknowledgements
                        Self-Defending Software   4
Architecture




               Self-Defending Software   5
ad hoc mode (IBSS)



                           STATION
                                                                Main
                                                           Charactéristics :
                                                             • Network ID
                                                                (SSID)
    STATION


                                                            • Transmission
                                                                Channel
                                     STATION

                                                              • Security
                                                             Mechanisms
              STATION                                         • Topology

                        IBSS


                                 Self-Defending Software                       6
Ad Hoc Networks Characteristics
 Ad hoc network :




 Require new Routing Protocols taking into account ad hoc net charac
 teristics:
    No infrastructure
    Mobility
    Low bandwidth
    Energy limitation


           Convergence des protocoles de routage dans les réseaux Ad hoc   7
Applications
 Conferencing
 Home networking
 Community networking
 Military Combat networking
 Relief organization (secours)
 Catastrophy management
 Specialized ad-hoc nets:
   Mesh Networks
   Sensor networks
   Vehicule Ad-hoc neworks : VANET



        Convergence des protocoles de routage dans les réseaux Ad hoc   8
Environnement Physique
 Notion de Connexion
 Problème d'Interférence
 Problème du Nœud Caché




       Convergence des protocoles de routage dans les réseaux Ad hoc   9
Routing Protocols

 Proactive routing protocols: DSDV, OLSR

 Reactive routing protocols: AODV, DSR

 Hybrid routing protocols: ZRP, cluster-based

 MMDV (Multipath and MPR based AODV) developed in the

 Cristal laboratory




         Convergence des protocoles de routage dans les réseaux Ad hoc   10
Routing Protocols

                          Routing Protocols:
                               3 classes


            Proactive                   Hybrid           Reactive/ on
                                                          demand

     Distance           Link           ZRP             DSR
      Vector            State                          AODV
                                                       TORA
     DSDV            OLSR                              DYMO
                     TBRPF
                     FSR
                     STAR


      Convergence des protocoles de routage dans les réseaux Ad hoc     11
Proactive Protocols
 Routes are established in advance
    May send packets immediately
    But too much overhead

 Deux major methods:
    Distance Vector:
       Next node to destination
       Example: DSDV
    Link State
       Network Topology
       Example: OLSR, TBRPF




         Convergence des protocoles de routage dans les réseaux Ad hoc   12
DSDV
Preserve simplicity of RIP protocol

Each Node keeps a Routing table with entries to all destinations:
   destination node, distance (in hops), next node, sequence number, life-time..

Periodical exchange of routing information (Distance vectors) with
neighbors:
   Possible optimization by sending reduced tables containing changes and sometime
   s the whole table
Table Update:
   Upon reception of a distance vector from a neighbour, each node compares for ea
   ch destination:
       If new seq number is higher then update routing entry
       If new seq number is equal to existing seq number update entry only if new distance is sm
       aller than existing one
       If new seq number is smaller than existing one then discard this information (no change)
Update period: because of mobility there are frequent changes in top
ology -- Small update period --large overhead


         Convergence des protocoles de routage dans les réseaux Ad hoc                 13
DSDV: Change of Topology
 If a Node Detect That a Link with a Neighbor is Lost ( at level
 2 with hello messages of Beacon or at level 3 no reception of r
 outing Tables)
 It sets hop distance to infinity (large number) to that entry an
 d to all entries that use that node as next hop
 A new sequence number is set: old-sequence number of that e
 ntry + 1 (this is the only time that a node is allowed to change
 the Seq number of another node
 Broadcast the RT


 Note that that if there is a good path for some nodes it will be
 recovered through the exchange of tables



         Convergence des protocoles de routage dans les réseaux Ad hoc   14
DSDV: Improvements
 For large networks: use 2 type or routing information
 Full dump: Full Routing Table
 Incremental: Carry only Changes that occured since last full
 dump
 Send Full Dump less frequently and use in between Increment
 al routing information


 Conclusion
    Simple routing algorithm
    Not efficient




          Convergence des protocoles de routage dans les réseaux Ad hoc   15
OLSR
 Optimized Link State Routing Protocol [CLA03]
      Project Hipercom, INRIA
      T. Clausen, P. Jacquet (RFC 3626) October 2003

 Proactive, Link State

      Each node must have full information on Topology

      Each node must send routing information to all nodes Flooding

 Multipoint Relays (MPR) to
      Selection of subset of neighbors to forward « routing » packets
     reduce flooding




          Convergence des protocoles de routage dans les réseaux Ad hoc   16
OLSR - MPR

Several
copies                                                                        MPR
                                                     
                                                         
                                                          
                                                   
                                                          
        
                                                         
                                                            
                                                  
                                                          
          Simple flooding                                     flooding through MPRs


             Convergence des protocoles de routage dans les réseaux Ad hoc    17
    OLSR – MS
     MS : Multipoint Relay Selector
        MS(N) : Set of nodes that chose N as their MPR.




     Example: MPR(4) = { 3, 6 }                                  MS(3) = {…, 4, …}
                                                                 MS(6) = {…, 4, …}

                                                                     4
             4                                                                       6
                                   6                   1
1

                                                                                 5            7
                          5                    7                 3
         3                                             2
2


                 Convergence des protocoles de routage dans les réseaux Ad hoc           18
Choice of MPRs
 Algorithm


 1/ Select all neighbors (1-hop) that are unique neighbors to 2-
 hop neighbors
 2/ Eeliminate the 2-hop neighbors connected to the set of
 MPR nodes
 3/Find among the neighbors the node that allow to reach the
 largest number of 2-hop nodes and add it to the set of MPRs
 and eliminate the 2-hop nodes reached by the new selected M
 PR
 4/ Repeat step 3 until all 2-hop neigbors are eliminated (cover
 ed)



         Convergence des protocoles de routage dans les réseaux Ad hoc   19
OLSR – MPR
 MPR : Multipoint Relay
    Each node N selects a set of nodes MPR(N) among his neighbors. This
    Set must cover all nodes at 2 hops from N

    Neighbors that do not belong to MPR(N) process the control packets co
    ming from N but do not forward them


        How would a neighbor of N know that it
        belongs or not to MPR(N)?

         Keep a List MS (Multipoint Relay Selector)




        Convergence des protocoles de routage dans les réseaux Ad hoc   20
OLSR – Messages
 Messages transmitted periodically:
    HELLO (every 2seconds)

          Contain list of neighbors as well as the types of links (Symetric, Asymetric).

          Allow to select MPRs.

          Used to determine neighbor table

    TC :Topology Control (every 2seconds)

          Allow to declare MPR’s in the whole network

          Transmitted by MPRs

          Used to determine topology tables

    MID
          Multi interface



            Convergence des protocoles de routage dans les réseaux Ad hoc         21
OLSR –HELLO
       A                                                                B


               A doesn’t hear B. Hello packet of A is empty


              B hears A. Hello packet of B contains A with status:
                                   asymetric


       A hears B and knows that B can hear him. Hello packet of A
                   contains B with status: symetric


           B hears A and knows that A can hear him. Hello packet o
                     f B contains A with status: symetric




  Hello(N)={List of Neighbors, type of link (sym, asym, MPR or lost)}

        Convergence des protocoles de routage dans les réseaux Ad hoc       22
OLSR –HELLO
 Neighbor discovery

 HELLO messages are not relayed (TTL=1)

 Using the list of neighbors received in HELLO messages, each node N
 can determine the list of neighbors at 2 hops and then determine its
 list of MPR(N).


            For node 4:
            V(1) = {2}                       4
            V(3) = {2,5}        1                             6
            V(5) = {3,6}
            V(6) = {5,7}                                                  7
                                         3            5
            MPR(4) ={3,6}       2


          Convergence des protocoles de routage dans les réseaux Ad hoc       23
OLSR – Heuristic to determine MPR nodes
                                  4
                                                   6              Neighbor   Number of 2
                     1
                                                                                 Hop Nodes
                                           5                7     5          0
                              3
                    2                                             3          1
                                                                  1          1

 Step 1:
    MPR(4)={}
    Add neighbors that uniquely connect to 2 hop neighbors of 4
        MPR(4)={6}
 Step 2:
    While there exists 2 hop neighbors not covered by nodes in MPR(4), add
    the neighbor that covers the largest number of 2 hop neighbors
      MPR(4)={6,3}


           Convergence des protocoles de routage dans les réseaux Ad hoc            24
OLSR – TC
 TC (Topology Control) messages are periodically broadcasted
 in the entire network

 Only MPR nodes (i.e. MS not empty) broadcast TC messages :
    List of MS (partial information on links)

    Sequence Number (to avoid using obsolete information)

 All nodes N process TC messages

 Using TC messages, each node determines a topological table
 That will allow it to compute the routing table




          Convergence des protocoles de routage dans les réseaux Ad hoc   25
OLSR – Tables
 Each Node maintains:
   Neighbor data base
      Table: direct neighbors

      Table: 2 hop neighbors.

      List of MPRs.

      List of MPR Selectors (MS)
   Topology Base
      Topology Table
                         T_dest               T_last               T_seq              T_time
      Routing Table
                         Destination Adress   adress of an MPR     Sequence           Time-life of this inform
                                              of the destination   Number             ation.




                         R_dest               R_next               R_dist                 R_if_id

                         destination adress   Next node to the     distance in hops       interface of local
                                              destination                                 node


        Convergence des protocoles de routage dans les réseaux Ad hoc                               26
Update of Routing Table RT
 RT is computed from Table of Neighbors and Topology Table
 Topology Table is created from the received Topology Control Messages
 All Nodes selected as MPRs broadcast periodically their MPS Selector (MS)
 Update RT if there is a change in Neighbors or in the TT:
 1/ Delete all entries from RT
 2/ Add to RT all neighbors with symetric link status
                          R_Next = R_dest, R_dist=1
 3/Repeat 4 begin with R_current-dist=1, stop if no more nodes to add
 4/ For each entry in TT which verifes:
      It does not belong to RT
      T_Last of that node is a destination in RT with distance = R_current-dist
  Then create an entry for that node in RT such that:
      R_Dest = T_Dest (of that Node)
      R_Next = T_Last
      R_Dist = R_current-dist + 1
  Increase R_current-dist by one
 5/ Delete entries not used in TT


             Convergence des protocoles de routage dans les réseaux Ad hoc        27
OLSR – Example
                                                                                               MPR(E)={D,F,G}
                            Hello(B; A; sym; D; mpr; E;assy)
                                              B

                                                  Hello(E ; - ; -)
                                                MS(E)={D;B;F;G}
                                                TC(E)={D;B;F;G}
                            A            Hello(E; F; mpr; G; mpr; D;mpr;B;sym)
                                                      E           F
                                          D
                          TC(D)={E;C,A,B}
                            MS(D)={E;C,A,B}                                       I


                                     C                     G          H




 TT(A)                                                                TR(A)
 T_des   T_last   T_seq     T_time                                        R_des       R_next   R_dist   R_if_id
 D       E                                                                B           B        1
 B       E
                                                                          D           D        1
 F       E
                    Assume                                            C         D
                                  that E just connects to the network at this instant          2
 G       E
                      E sends an empty Hello message to all its neighbors D
                                                                   E                           2
 E       D
                                                                          F           D        3
 C       D
                                                                          G           D        3
 …       …        …         ...
                                                                          …



             Convergence des protocoles de routage dans les réseaux Ad hoc                               28
OLSR – Synthesis

 Based on MPR concept( Multipoint Relays)

 Optimization of diffusion overhead
    Diffusion of packets through MPRs
         Reduce Overhead

    A control packet contains only a subset of neighbors
           less Overhead

          Nodes know a partial topology

         Computed roads are optimal




 Routes are immediatly available




            Convergence des protocoles de routage dans les réseaux Ad hoc   29
OLSR - Drawbacks
 Control Messages sent periodically
    HELLO_INTERVAL= 2 sec
    TC_INTERVAL= 5 sec

 doesn’t react well to node mobility, solution?
     Increase frequency of hello messages
       increase overhead
       risk of congestion


     Decrease of periodicity of Hello messages
       weak adaptation to topology changes
       List of MPRs obsolete
       erroneous control information


Fast-OLSR
     Dynamic OLSR (fast OLSR) (node in one of 2 states fast or normal))


        Convergence des protocoles de routage dans les réseaux Ad hoc     30
Reactive Protocols
 Routes are established on Demand
   No control traffic if routes are not used
   But packet is slowed down if route doesn’t exist!


 Two major techniques:
   Source Routing: the source indicates the path to be followed by a
   packet to reach a destination (DSR)
   The source forwards the packet to the next node towards the dest
   ination (AODV)




         Convergence des protocoles de routage dans les réseaux Ad hoc   31
AODV – Presentation
 Ad hoc On-Demand Distance Vector
     C. Perkins, E. Belding-Royer et S. Das (RFC 3561) july 2003

 Reactive, distance vector

 Each Node keeps a Routing table with entries to some destinations:
    dest node, next node, distance (in hops), dest sequence No , life-time, precursors

 Upon arrival of a packet:
    If entry for destination exists on the table (and not obsolete) then send packet
    If no entry then establish a road to destination

 Route Establishment
    Route Request, RREQ (Broadcast) with an ID to avoid duplications
    Route Reply, RREP (unicast)
    Route Error,RERR (unicast) in case of link failure on the established path


           Convergence des protocoles de routage dans les réseaux Ad hoc        32
    AODV – Example 1

                             RREP
                             RREQ     B

                      RREQ
Dest
Des    N.H
       N.H   Dist
             Mét         A
                                              E            F
F      B     3                    D
                                                                     RREQ
                                             RREP
                                             RREQ         RREP
                               RREQ                                     H


                              C                     J            I   RREQ
                                                        RREQ



                                          Broadcast of RREQ’s




                               Process of route discovery
                             Response to a route discovery

                    Convergence des protocoles de routage dans les réseaux Ad hoc   33
    AODV – Example 2
                             A       A   1       E
                                                 F
                             F       E   2       A

                            RREP
                             RERR
                            RREQ B
                                         A
                                         A       B
                                                 B     2
                                                       2     F
                     RREQ
F    B   3              A
                                         X
                                         F       F    A1    EA       3
                                                                         A   E   3
                                                 E               F
                                 D
                                             RERR
                                             RREP
                                             RREQ           RREP             H


                             C                         J             I

                                                     RREQ


                   Assume
             RREQ broadcast all tables are empty
                    Routing Table
             RREQ will be ignored by nodes if {adresse ip,Broadcast_ID} already exists in table of
         « Broadcast_ID »Destination
                         Next node
                            Distance in Hops
                            List of precursors
                            …


                  Convergence des protocoles de routage dans les réseaux Ad hoc                  34
AODV – Recap
 Advantages: expect
   Smaller routing tables
   Better Adaptation to topology changes


 Drawbacks:
   RREQ Flooding


 Improvements:                                          B

   AODV-PA:
                                           A
      Path Accumulation                                         E        F
                                                    D
   AODV multipath:                                                                    H
      Multiple Paths
                                                C                   J        I
 Drawbacks:
   RREQ Flooding
         Convergence des protocoles de routage dans les réseaux Ad hoc           35
DSR – Presentation
 Dynamic Source Routing Protocol: David Johnson et al. (INTE
 RNET−DRAFT)
    The source specifies the entire path to the destination in the packet hea
    der
 Each Node keeps a Cash but not a Routing table
 Upon arrival of a packet:
    If path for destination exists in the Cash (and not obsolete) then send pac
    ket with path in header
    If no entry then establish a path to destination
 Route Establishment
                                        RREQ’s cause
   Route Request, RREQ (Broadcast) with an ID to large duplications
                                            Overheads
                                                     avoid
   Route Reply, RREP (unicast)
   Route Error, RERR (unicast) in case of link failure on the
   established path


          Convergence des protocoles de routage dans les réseaux Ad hoc   36
 DSR – Example 1

                         RREQ[A;B]          Chemin         Mét
                                            Chemin      Mét
                             B              F-E-D-A        3
                                            F-E-D-A     3
                RREQ[A]
                                            H-I-J-E-D-A
                                RREP[F-E-D-A]              5
                                  RREQ[A;D;E]
                                            RREP[F-E-D-A]
                   A
                       RREQ[A;D]
                       RREP[F-E-D-A]
Chemin    Mét               D
                                        E          F


A-D-E-F   3                                                    H   RREQ[A;D;E;J;I;H]

                        C                   J          I

                                             RREQ[A;D;E;J;I]
                                     RREQ[A;D;E;J]

                                  Path Accumulation




                       Process to a route discovery
                      Response of route discovery

              Convergence des protocoles de routage dans les réseaux Ad hoc            37
 DSR – Example 2

                               RREQ(A;B)
                                                            Chemin       Mét
                                      B
                     RREQ(A)                           F-E-D-A           3
                        A RREP(F-H-I-J-E-D-A)
                                       RREQ(A;D;E)
                                                 RREP(F-E-D-A)
                                   RREP(F-H-I-J-E-D-A)
                           RREQ(A;D)RREP(F-E-D-A)
                           RREP(F-E-D-A)
                                               E           F
                                  D
Path
Chemin          Dist
                Mét
                                                                        H
A-D-E-J-I-H-F   6                         RREP(F-H-I-J-E-D-A)
A-D-E-F         3             C                     J           I


                        RREQ(A;D;C)           Chemin       Mét
                                              J-I-H-F      3
                                              J-E-D-A      3



                RREQ is ignored if :
              Node path to the destination destination
             {adresschooses shortest path toin of RREQs recently received}.
      If a node has aip, RREQ_ID} exists in listits cash then it concatenates the path it obtained with th
             the address of sends a reply to the source.
      e one in the cash andthe current node exists in the path of the RREQ.



                    Convergence des protocoles de routage dans les réseaux Ad hoc                    38
DSR – Recap
 Advantages:
   Easy to implement
   Multiple Paths


 Drawbacks:
                                                              B


   Agressive usage of cashes                     A
                                                                     E         F
   Path validity                                          D
                                                                                            H
   Cash Pollution
                                                      C                    J       I

 Improvements:
   DSR*-DR:
       Does not allow intermediate nodes to reply using information in their cash
   DSR*:
       Introduce Path lifetime

           Convergence des protocoles de routage dans les réseaux Ad hoc               39
Important Routing Features


        Features                   Protocol                     Characteristic
MPR flooding                                        Minimize flooding
                               OLSR

Detection of high mobility                          Adapt to topology changes
                               Fast-OLSR

Path Accumulation                                   More routing information
                               DSR

Multiple Routes                                     Adapt to topology changes
                               DSR/TBRPF




            Convergence des protocoles de routage dans les réseaux Ad hoc        40
Work at Cristal Lab: AODV Optimisation
Approch


   AODV+MPR
     Optimization of RREQ flooding
   AODV+MPR Dynamic (fast OlSR feature)
     MPR with detection of high mobility
   AODV+PA
     Path Accumulation
   AODV multi chemin
     Multiple Paths




       Convergence des protocoles de routage dans les réseaux Ad hoc   41
AODV + MPR
 Modification of AODV Hello Messages :

 Processing of Hello Messages :
     Update Neighbor Table
     Update Routing Table
    Protocole hybride


 Selection of MPR list
     Périodic




           Convergence des protocoles de routage dans les réseaux Ad hoc   42
AODV + « Dynamic » MPR
 Detection of high mobility:
    Changes in neigbor table (Fast-OLSR)
    Threshold=1/5


 If a node detects a high mobility :
    Changes to Rapid State
    Increase frequecy of Hello messages
  Reduce time of computation of MPR List




          Convergence des protocoles de routage dans les réseaux Ad hoc   43
AODV+PA
Path Accumulation
  Add sequence of traversed nodes in routing tables


  Modify the structure of RREQ and RREP
     Add Adresses of intermediary nodes


  Processing of RREQ and RREP
     Update routing table
     Add entries to intermediary nodes




       Convergence des protocoles de routage dans les réseaux Ad hoc   44
AODV multiple path
    Multiple path :
       Maintain 2 « disjoint » paths
     Minimize probability of path failures
                                                       S               A       B       C            D

    Minimize number of nodes in common for the 2 paths
       AODV Multipath Protocol
       Add JointCount (JC) field to RREP messages
       Each common node increases JC
                                                                       1
                                                                   B
   Threshold <=2/5 to retain a path
                                                                           1           0
                                                   A           1
                                                               D           E           F

                                                                                                    H

                                                           C                       J       I


             Convergence des protocoles de routage dans les réseaux Ad hoc                     45
Performance Evaluation
Performance Variables:
  Packet delivery rate (received packets / transmitted packets)
  End-to end delay (Response time)
  Routing overhead
     Normalized overhead (Routing packets generated/data packets received)
     Routing Charge (Kbit/s)


Implementation of the protocoles under NS-2 simulator
Run simulation
  Measurement at steady state
  Compute confidence intervalls
  Use batch mean method to stop simulation




        Convergence des protocoles de routage dans les réseaux Ad hoc   46
Simulation Scenarios
                             scénario 1       scénario 2       Scénario 3

     Nombre de nœuds               50              100              100

     Aire (m2)                1000 * 750       1500 * 1000       700 * 700

     Densité (nœud / m2)       1 / 15000        1 / 15000         1 / 4900
                                Random           Random           Random
     Modèle de mobilité
                                waypoint         waypoint         waypoint
     Temps de pause (s)            30               30                  30

      Vitesse max (m/s)          0 - 20           0 - 20                10

     Capacité des liens         2 Mb/s           2 Mb/s           2 Mb/s
     Nombre de
                                   20               20             10-100
     connexion CBR
     Débit                    4 paquets/s      4 paquets/s      4 paquets/s



        Convergence des protocoles de routage dans les réseaux Ad hoc         47
                                                                                                                   scénario 3
                                                                                                                   scénario 1
                                                                                                                   Scénario 2


Delivery Rate
                                                                                             Nombre de nœuds           50
                                                                                                                      100

                                                                                             Aire (m2)              1000 700
                                                                                                                    700 750
                                                                                                                   1500 **1000
                                                                                                               2
                                                                                             Densité (nœud / m )     1 15000
                                                                                                                    1 ///15000
                                                                                                                          4900
                                                                                                                    Random
                                                                                                                    Random
                                                                                             Modèle de mobilité
                                                                                                                    waypoint
                                                                                                                    waypoint
     70
    100
                                                                                             Temps de pause (s)        30
                                                                                                                       30
                                                                               AODV
                                                                         AODV +MPR            Vitesse max (m/s)      0 - 20
                                                                                                                     0 10
                                                                                                                       - 20
    90                                                               AODV +DynMPR
    65
    95                                                                     AODV +PA                                  2 Mb/s
                                                                                             Capacité des liens        Mb/s
                                                                     Multipath A ODV
     80                                                                                      Nombre de                 20
                                                                                                                       20
                                                                                                                     10-100
                                                                                             connexion CBR
    60
    90                                                                                       Débit de donnée       4 paquets/s
                                                                                                                     paquets/s
     70


    55
    85
    60


    50
    50
    80


     40
    45
    75

     30

    40
    70
    20


    10
    35
    65
       10
        0     20     30 5   40      50    10    60      70   15 80          90         20
                                                                                       100
                                   Max of connections
                                 Number speed (m/s)




            Convergence des protocoles de routage dans les réseaux Ad hoc                                48
Synthesis of results
    Delivery rate:                                                   Low speed            Low traffic   High speed          High traffic
                                                                                             load                              load

                          AODV+PA                                       C                     C              C                   C
                          AODV+MPR                                      B                     B              C                   C

                          AODV+DynMPR
                                                                        A                     A              B                   B

                          AODV multi
                                                                        C                     C              A                   A
                          chemin
                                                                                 70
                                                                                                                                     AODV +DynMPR
                                                                                                                                     Multipath A ODV


                                                                                 65




    2 best features
                                                                                 60


                                    Pack et delivery frac tion (%)




        Dynamic MPR
                                                                                 55
    
       Multiple path                                                            50




   MMDV (add 2 features to AODV)                                                45




                                                                                 40
                                                                                      0             5           10              15                     20
                                                                                                          Max speed (m/s)



             Convergence des protocoles de routage dans les réseaux Ad hoc                                                      49
MMDV
MMDV: Multipath and MPR based AODV


Hybrid Protocol
   Proactive Phase :
      Periodic update sof routes to neighbours at up to 2 hops (hello messages)
      Periodic computation of MPRs
   Reactive Phase :
      Establishment of a new Path (RREQ/RREP)
      Compute « disjoint » paths


Two zones
   Zone within 2 hops (proactive routing)
   Zone beyond 2 hops (reactive routing)



        Convergence des protocoles de routage dans les réseaux Ad hoc       50
MMDV- Example

                                   K


                               B


                  A                             RERR
                           D           E          F

                                                             H

                       C                   J           I




     Convergence des protocoles de routage dans les réseaux Ad hoc   51
                                                                                                                     scénario 3
                                                                                                                     scénario 1
                                                                                                                     Scénario 2


Delivery Rate                                                                                  Nombre de nœuds

                                                                                                      2
                                                                                               Aire (m )
                                                                                                                         50
                                                                                                                        100

                                                                                                                      1000 700
                                                                                                                      700 750
                                                                                                                     1500 **1000

                                                                                               Densité (nœud / m2)     1 15000
                                                                                                                      1 ///15000
                                                                                                                            4900
                                                                                                                      Random
                                                                                                                      Random
     100
      70                                                                                       Modèle de mobilité
                                                                                                                      waypoint
                                                                                                                      waypoint
                                                                        AODV +DynMPR
                                                                                               Temps de pause (s)        30
                                                                                                                         30
                                                                        AODV multipath
     90                                                                     MMAODV                                     0 10
                                                                                                Vitesse max (m/s)      0 - 20
                                                                                                                         - 20
     65
     95                                                                                        Capacité des liens      2 Mb/s
                                                                                                                         Mb/s
     80                                                                                        Nombre de                 20
                                                                                                                         20
                                                                                                                       10-100
                                                                                               connexion CBR
     60                                                                                        Débit de donnée       4 paquets/s
                                                                                                                       paquets/s
     70
     90


     60
     55


     85
     50
     50

     40
     80
     45
     30



     40
     20
     75
        0
       10        20     30 5   40      50    10    60      70   15 80          90        20
                                                                                         100
                                      Max of connections
                                    Number speed (m/s)




            Convergence des protocoles de routage dans les réseaux Ad hoc                                    52
                                                                                                                 scénario 3
                                                                                                                 scénario 1
                                                                                                                 Scénario 2


Routing Overhead (load)                                                                    Nombre de nœuds

                                                                                                  2
                                                                                           Aire (m )
                                                                                                                     50
                                                                                                                    100

                                                                                                                  1000 700
                                                                                                                  700 750
                                                                                                                 1500 **1000

                                                                                           Densité (nœud / m2)     1 15000
                                                                                                                  1 ///15000
                                                                                                                        4900
                                                                                                                  Random
                                                                                                                  Random
   4.5
   3.4
   2.6                                                                                     Modèle de mobilité
                                                                                                                  waypoint
                                                                                                                  waypoint
                                                                    AODV +DynMPR           Temps de pause (s)        30
                                                                                                                     30
                                                                    AODV multipath
     4
   3.2                                                                  MMAODV                                     0 - 20
                                                                                                                   0 10
                                                                                                                     - 20
                                                                                            Vitesse max (m/s)
   2.4
                                                                                           Capacité des liens      2 Mb/s
                                                                                                                     Mb/s
     3
   3.5
                                                                                           Nombre de                 20
                                                                                                                     20
                                                                                                                   10-100
   2.2                                                                                     connexion CBR
   2.8
     3                                                                                     Débit de donnée       4 paquets/s
                                                                                                                   paquets/s


     2
   2.6
   2.5


     2
   2.4
   1.8


   2.2
   1.5
   1.6

    2
    1

   1.4
   1.8
   0.5


     0
   1.6
   1.2
      10
       0     20     30 5   40      50    10    60      70   15 80          90        100
                                                                                     20
                                  Max of connections
                                Number speed (m/s)




           Convergence des protocoles de routage dans les réseaux Ad hoc                                 53
                                                                                                                   scénario 1         Scénario 3
                                                                                                                                      scénario 2


MMDV vs AODV                                                                                              Nombre de nœuds
                                                                                             Nombre de nœuds

                                                                                             Aire (m2)
                                                                                                                    50

                                                                                                             Aire (m21000 * 750
                                                                                                                     )
                                                                                                                                         100
                                                                                                                                         100

                                                                                                                                       700 * 700
                                                                                                                                      1500 * 1000
                                                                                                                                  2
                                                                                                             m 2)
                                                                                             Densité (nœud / Densité (nœud / m )
                                                                                                                     1 / 15000               4900
                                                                                                                                       11/ /15000
                                                                                                                   Random              Random
                                                                                                                                       Random
                                                                                                            Modèle de mobilité
                                                                                             Modèle de mobilité
  100                                                                                                              waypoint            waypoint
                                                                                                                                       waypoint
                                                                  MMDV   (scenario3)
                                                                         (scenario1)         Temps de pauseTemps de pause (s)
                                                                                                           (s)       30                   30
                                                                                                                                          30
                                                                  AODV   (scenario3)
                                                                         (scenario1)
  90                                                              MMDV   (scenario2)                                 0 - (m/s)
                                                                                                             Vitesse max20
                                                                                              Vitesse max (m/s)                           10
                                                                                                                                        0 - 20
  90                                                              AODV   (scenario2)
                                                                                                                      des liens
                                                                                                             Capacité 2 Mb/s
                                                                                             Capacité des liens                        2 Mb/s
                                                                                                                                       2 Mb/s
   80
                                                                                             Nombre de     Nombre de
                                                                                                                     20                 10-100
                                                                                                                                         20
  80                                                                                         connexion CBR connexion CBR

   70                                                                                        Débit de donnée Débit de donnée
                                                                                                                    4 paquets/s       4 paquets/s
                                                                                                                                      4 paquets/s


  70
  60


  50
  60


   40
  50

   30

  40
  20


  10
  30
     10
     0    20     30 5   40        50    10    60         70   15 80          90        100
                                                                                       20
                                Vites se de connexions
                             Nombre max max (m/s)




          Convergence des protocoles de routage dans les réseaux Ad hoc                                                   54
Conclusion
 Many routing protocols
    MMDV is interesting but
    4 are in the final standardization process


 More work is required at the network level: autoconfiguration
 (addressing schemes)
 More work is required at the transport level:UDP, TCP, others?
 Quality of Service
 Security
 Killer Application
 Real deployments
 Mesh Networks look more promissing!!


          Convergence des protocoles de routage dans les réseaux Ad hoc   55

								
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