Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

cluster based routing protocol for ad hoc networks

This compare and evaluate two routing protocols DSR and CBRP in ad hoc networks. DSR is based on flat topology and CBRP is of cluster based. Both are compared in different number of scenarios and their performances are compared in terms of pdf, channel utilization, nrl, average end to end delay and control overheads.

  • Be the first to comment

  • Be the first to like this

cluster based routing protocol for ad hoc networks

  1. 1. Dr. N.S.Yadav Assoc.Prof. www.nshubforum.com Department of Computer Science & Engineering Sri Balaji College of Engineering & Technology, Jaipur Performance Evaluation of Cluster Based Routing Protocol in Ad hoc Networks 1
  2. 2. Contents 2  Introduction  Routing in mobile adhoc networks  Performance evaluation of CBRP  Conclusions and future scope
  3. 3. Introduction 3  mobile ad hoc network is a collection of mobile nodes that utilize multi- hop radio relaying and are capable of operating without any support from fixed infrastructure  Various authors defined MANET in many different ways and a more precise definition* may be taken as reference, which states it as: “MANET is an autonomous system of mobile routers (and associated hosts) connected by wireless links - the union of which form an arbitrary graph. The routers are free to move randomly and organize themselves arbitrarily; thus, the network’s wireless topology may change rapidly and unpredictably. Such a network may operate in a stand-alone fashion, or may be connected to the larger Internet”. *Joseph Macker and Scott Corson, “Mobile ad-hoc networks (manet)”, http://www.ietf.org/proceedings/01dec/183.htm, December 2001.
  4. 4. Characteristics of Ad Hoc Networks 4 The most salient characteristics which should be considered by protocol designers were addressed within the MANET working group, listed in RFC 2501 and are summarized here:  Distributed Operation  Dynamic Topology  Multi Hop Communications  Changing Link Qualities  Dependence on Battery life
  5. 5. Applications 5  Military applications  Collaborative and distributed computing  Emergency operations  Wireless sensor networks  Hybrid wireless networks
  6. 6. Routing in mobile ad hoc networks 6 The routing protocol has two main functions:  Selection of routes for various source destination pair  The delivery of messages to their correct destination
  7. 7. Characteristics of routing protocols 7  fully distributed  adapt to frequent topology changes  loop-free and free from stale routes  utilize both unidirectional and bi-directional links  localized and involve minimum number of nodes  minimize the number of packet collisions  converge to optimal routes quickly  use scarce resources efficiently  utilize multiple routes  incorporate quality of service (QoS)
  8. 8. Routing classification 8 Routing Protocols for MANET Based on Information Update Mechanism Based on Topology Reactive FlatProactive Cluster Based
  9. 9. Based on Information Update Mechanism 9  Proactive or table- driven routing protocols  Every node maintains the network topology information in the form of routing tables, example DSDV  Reactive or on- demand routing protocols  Maintain routes only if needed example DSR  Hybrid protocols  Combine the best features of the above two categories example ZRP
  10. 10. Based on Topology 10  In a flat structure, all nodes in a network are at the same level and have the same capability and responsibility. Flat structure routing is simple and efficient for small networks. Example DSR  In cluster-based routing the nodes in the network are dynamically organized into partitions called clusters and then the clusters are aggregated again into larger partitions called superclusters and so on. Example CBRP
  11. 11. Clustering in Ad hoc network 11  Dynamic routing plays an important role in the performance of a Mobile Ad Hoc Networks (MANET).  A flat structure exclusively based on proactive or reactive routing schemes cannot perform well in a large dynamic MANET  The communication overhead of proactive routing protocols is O(n2), where n is the total number of mobile terminals in a network.  For a reactive routing scheme, the disturbing RREQ (route request) and the considerable route setup delay become intolerable in the presence of both a large number of nodes and mobility.  Consequently, a hierarchical architecture (cluster- based) is essential for achieving a basic performance guarantee in a large- scale MANET.
  12. 12. Cluster Structure 12 CM CM CH CM CM CM CH CH GW GW GW CM GW CH Cluster member node Gateway node Cluster- Head node member node
  13. 13. Clustering in Ad hoc network 13  In a clustering scheme the nodes in a adhoc network are divided into different virtual groups, and they are allocated to the cluster according to some rules.  Under a cluster structure, mobile nodes may be assigned a different status or function, such as clusterhead, clustergateway, or clustermember.  A clusterhead normally serves as a local coordinator for its cluster, performing intra-cluster transmission arrangement, data forwarding, and so on.  A clustergateway is a non-clusterhead node with inter-cluster links, so it can access neighboring clusters and forward information between clusters.  A clustermember is usually called an ordinary node, which is a non- clusterhead node without any inter-cluster links
  14. 14. Motivation 14  Clustering is important for a network to achieve scalability in presence of a large number of mobile nodes and high mobility  However, constructing and maintaining a cluster structure usually requires additional control overhead compared to a flat-based structure in an ad hoc wireless network.  This additional control overhead involved in clustering is a key issue to validate the effectiveness and scalability enhancement of a cluster structure.
  15. 15. Contribution 15  A flat architecture based Dynamic Source Routing (DSR), and cluster architecture based Cluster Based Routing Protocol (CBRP) are evaluated and compared in terms of  packet delivery fraction,  normalized routing load,  average end to end delay,  channel utilization and  control overhead in terms of packets and bytes by varying number of nodes per sq. km, traffic sources, mobility, speed and network load. It is shown through results that CBRP is a better routing protocol in the presence of large number of nodes, increased network traffic and load.
  16. 16. DSR – Dynamic source routing 16  on-demand routing protocol designed to restrict the bandwidth consumed by control packets by eliminating the periodic table-update messages required in the table-driven approach.  beacon-less and hence does not require periodic hello packet.  When node S wants to send a packet to node D, but does not know a route to D, node S initiates a route discovery.  Source node S floods Route Request (RREQ)  Each node appends own identifier when forwarding RREQ  Destination D on receiving first RREQ, sends a Route Reply (RREP)  RREP is sent on a route obtained by reversing the route appended to received RREQ  If any link on a source route is broken, the source node is notified using a route error RERR
  17. 17. CBRP - Cluster Based Routing Protocol 17  In CBRP the nodes of a wireless network are divided into clusters.  The diameter of a cluster is only two hops and clusters can be disjoint or overlapping.  Each cluster elects one node as the clusterhead, responsible for the routing process.  Clusterheads communicate with each other through gateway nodes.
  18. 18. Operation of CBRP 18 The operation of CBRP can be divided in three phases:  Cluster formation  Routing process  Cluster maintenance
  19. 19. Cluster Formation 19  At any time, a node is in one of the three states: a cluster member (CM), a cluster head (CH), or undecided (UNDECIDED).  When a node comes up, it enters the undecided state and broadcasts a Hello message.  When a cluster-head gets this hello message it responds with a triggered hello message immediately. When the undecided node gets this message, it sets its state to member.  If the undecided node times out, then it declares itself the cluster-head, if it has bi-directional link to some neighbor otherwise it remains in undecided state and repeats the process again.
  20. 20. 20 A node in undecided state changes its status to one of the three states: CH, CM or UNDECIDED as per the state transition diagram UNDECIDED STATE Receiving Hello from non –CH member Times out Receive Hello from CH Neighbor table Update u_timer Is neighbour table empty? YES Schedule new u_timer Send triggered Hello as CH Terminate u_timer Neighbor table as CM Update NO CH STATE CM STATE
  21. 21. 21 When two clusterheads are within transmission range of each other, the one satisfying the state transition diagram will continue in clusterhead CH state and the other will give up its role as CH and acquire the status of cluster member CM. Receive Hello from CH Set c_timer CH STATE Receiving Hello from non –CH member c_timer Neighbor table Update expires Is still in contention with other CH? NO YES CM STATE Send triggered Hello as CH Is my_CH_ID < Other CH_IDYES Send triggered hello as CM NO
  22. 22. 22 A node in cluster member CM state changes its status to one of the three states: CH, CM or UNDECIDED as per the state transition diagram Receive Hello Schedule u_timer CM STATE Last head lost NO YES CH STATE Send triggered Hello as CH Is my__ID < any_other_ID Update neighbor table UNDECIDED STATE
  23. 23. Routing process 23  The routing process works in two steps. First, it discovers a route from a source node S to a destination node D, afterwards it routes the packets.  On receiving the request a clusterhead checks to see if the destination is in its cluster.  When the destination receives the request packet, it replies back with the route that had been recorded in the request packet.  While forwarding the packet if a node detects a broken link it sends back an error message to the source and then uses local repair mechanism.
  24. 24. Comparison of DSR and CBRP Parameter DSR CBRP Routing structure Flat Cluster Hello messages No Yes Multiple routes Yes No Critical nodes No Yes Route maintained Route Cache Route table at cluster-Head Routing metric Shortest path or next available in route cache First available route Time complexity (route discovery) O (2D) O (2D) Time complexity (route maintenance) O (2D) O (2d) Communication complexity (route discovery) O (2N) O (2C) Communication complexity (route maintenance) O (2N) O (2n) Advantages Multiple routes, beacon less cluster heads exchange routing information Disadvantages Scalability problem, large delays Cluster maintenance Abbreviations: D = Diameter of the network N = Number of nodes in the Network d = Diameter of affected area C = Number of Clusters n = Number of affected nodes 24
  25. 25. Simulation Parameters Parameter Stage I Stage II Stage III Stage IV Number of nodes 150 150 150 30,60,90,120,150 Traffic type CBR (UDP) CBR (UDP) CBR (UDP) CBR (UDP) Traffic sources 30% of nodes 70% of nodes 30% of nodes 70% of nodes 10%,30%,50%,70%, 90% of nodes 30% of nodes 70% of nodes Simulation time 300s 300s 300s 300s Simulation area 2000 m x 500 m 2000 m x 500 m 2000 m x 500 m 2000 m x 500 m Transmission range 250 m 250 m 250 m 250 m Node movement model Random waypoint Random waypoint Random waypoint Random waypoint Propagation model Two ray ground Two ray ground Two ray ground Two ray ground Data payload 512 bytes/packet 512 bytes/packet 512 bytes/packet 512 bytes/packet Packet rate 4 packets/sec 2,4,6,8,10 packets/sec 4 packets/sec 4 packets/sec Node pause time 0,60,120,180, 240,300 s 0s highest mobility 300 s lowest mobility 0s highest mobility 300 s lowest mobility 0s highest mobility 300 s lowest mobility Speed 10 m/s 10 m/s 10 m/s 10 m/s Bandwidth 2 Mb/s 2 Mb/s 2 Mb/s 2 Mb/s 25
  26. 26. Performance Metrics 26  Packet Delivery Fraction: The ratio of the data packets delivered to the destinations to those generated by the sources.  Channel utilization capacity: This metric gives the fraction of channel capacity used for data transmitted by the network and is computed as where PR is the number of data packets received by the destination nodes, SZ is the size of the data packets, SET is simulation end time and BW is the nominal channel bandwidth.   BWSET SZPR CU     
  27. 27. 27  Average end-to-end delay: This includes all possible delays caused by buffering during route discovery latency, queuing at the interface queue, retransmission delays at the MAC, and propagation and transfer times.  Normalized routing load: The number of routing packets transmitted per data packet delivered at the destination.  Control Overhead: The total number of non data packets transmitted by the protocol. It is an important measure for the scalability of a protocol. If a protocol requires sending many control packets, it will most likely cause congestion, collision, data delay and increase energy consumption in larger networks.
  28. 28. SIMULATION RESULTS 28
  29. 29. Influence of node mobility 29 To observe the effect of node mobility on the performance of DSR and CBRP for a network under different traffic scenarios a network of 150 nodes is simulated over a network area of size 2000m × 500 m with parameters listed in Table in stage I and the simulation results are presented in this section.
  30. 30. Packet Delivery Fraction 0 10 20 30 40 50 60 70 80 0 60 120 180 240 300 Pause time (sec) Packetdeliveryfraction(%) DSR CBRP 0 5 10 15 20 25 30 35 40 45 0 60 120 180 240 300 Pause time (sec) Packetdeliveryfraction(%) DSR CBRP 30 (a) 30% sources (b) 70% sources Packet delivery fraction as a function of Pause time and 30%, 70% traffic sources.
  31. 31. Channel Utilization 0 2 4 6 8 10 12 14 0 60 120 180 240 300 Pause time (sec) Channelutilization(%) DSR CBRP 0 2 4 6 8 10 12 14 16 18 0 60 120 180 240 300 Pause time (sec) Channelutilization(%) DSR CBRP 31 (a) 30% sources (b) 70% sources Channel utilization as a function of Pause time and 30%, 70% traffic sources.
  32. 32. Average End To End Delay 0 0.5 1 1.5 2 2.5 3 3.5 4 0 60 120 180 240 300 Pause time (sec) averageendtoenddelay(sec) DSR CBRP 0 1 2 3 4 5 6 7 8 9 0 60 120 180 240 300 Pause time (sec) averageendtoenddelay(sec) DSR CBRP 32 (a) 30% sources (b) 70% sources Average end to end delay as a function of Pause time and 30%, 70% traffic sources.
  33. 33. Normalized Routing Load 0 1 2 3 4 5 6 7 8 0 60 120 180 240 300 Pause time (sec) Normalizedroutingload DSR CBRP 0 2 4 6 8 10 12 14 16 18 20 0 60 120 180 240 300 Pause time (sec) Normalizedroutingload DSR CBRP 33 (a) 30% sources (b) 70% sources Normalized routing load as a function of Pause time and 30%, 70% traffic sources.
  34. 34. Control Overhead 0 10 20 30 40 50 60 70 80 90 0 60 120 180 240 300 Thousands Pause time (sec) Controloverhead(packets) DSR CBRP 0 20 40 60 80 100 120 140 160 180 0 60 120 180 240 300 Thousands Pause time (sec) Controloverhead(packets) DSR CBRP 0 1 2 3 4 5 6 7 0 60 120 180 240 300 Millions Pause time (sec) Controloverhead(Bytes) DSR CBRP 0 2 4 6 8 10 12 14 0 60 120 180 240 300 Millions Pause time (sec)Controloverhead(Bytes) DSR CBRP 34 (a) 30% sources (b) 70% sources Control Overhead as a function of Pause time and 30%, 70% traffic sources.
  35. 35. Influence of network load 35 In this section the results of the simulations carried out by varying the number of packets transmitted per second from 2 to 10 with two different pause times are presented separately with 30% and 70% of the nodes forming the traffic.
  36. 36. Packet Delivery Fraction 0 20 40 60 80 100 120 2 4 6 8 10 Packets per sec Packetdeliveryfraction(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 10 20 30 40 50 60 70 2 4 6 8 10 Packets per sec Packetdeliveryfraction(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 36 (a) 30% sources (b) 70% sources Packet delivery fraction as a function of load and 30%, 70% traffic sources.
  37. 37. Channel Utilization 0 2 4 6 8 10 12 14 16 18 2 4 6 8 10 Packets per sec Channelutilization(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 2 4 6 8 10 12 14 16 18 20 2 4 6 8 10 Packets per sec channelutilization(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 37 (a) 30% sources (b) 70% sources Channel utilization as a function of Load and 30%, 70% traffic sources.
  38. 38. Average End To End Delay 0 1 2 3 4 5 6 2 4 6 8 10 Packets per sec Averageendtoenddelay(sec) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 1 2 3 4 5 6 7 8 9 10 2 4 6 8 10 Packets per sec Averageendtoenddelay(sec) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 38 (a) 30% sources (b) 70% sources Average end to end delay as a function of Load and 30%, 70% traffic sources.
  39. 39. Normalized Routing Load 0 1 2 3 4 5 6 7 8 9 10 2 4 6 8 10 Packets per sec Normalizedroutingload DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 2 4 6 8 10 12 14 16 18 20 2 4 6 8 10 Packets per sec Normalizedroutingload DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 39 (a) 30% sources (b) 70% sources Normalized routing load as a function of Load and 30%, 70% traffic sources.
  40. 40. Control Overhead 0 20 40 60 80 100 1 2 3 4 5 Thousands Packets per sec ControlOverhead DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 20 40 60 80 100 120 140 160 180 2 4 6 8 10 Thousands Packets per sec Controloverhead DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 1 2 3 4 5 6 7 8 2 4 6 8 10 Millions Packets per sec Controloverhead(bytes) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 2 4 6 8 10 12 14 2 4 6 8 10 Millions Packets per sec Controloverhead(bytes) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 40 (a) 30% sources (b) 70% sources Control Overhead as a function of Load and 30%, 70% traffic sources.
  41. 41. Influence of traffic sources 41 To observe the effect of number of traffic sources on the performance of DSR and CBRP for a network, in constantly changing network topology and in static case, a network of 150 nodes is simulated over a network area of size 2000m × 500m with parameters listed in Simulation Table in stage-III and the number of nodes forming the traffic are increased from 15 to 135 in the step of 30 and the simulation results obtained are presented in this section.
  42. 42. Packet Delivery Fraction 42 0 20 40 60 80 100 120 15 45 75 105 135 Number of sources Packetdeliveryfraction(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s Packet delivery fraction as a function of Traffic sources in low and high mobility scenarios.
  43. 43. Channel Utilization 43 0 2 4 6 8 10 12 14 16 15 45 75 105 135 Number of sources Channelutilization(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s Channel utilization as a function of Traffic sources in low and high mobility scenarios.
  44. 44. Average End To End Delay 0 1 2 3 4 5 6 7 8 9 10 15 45 75 105 135 Number of sources Averageendtoenddelay(sec) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 44 Average end to end delay as a function of Traffic sources in low and high mobility scenarios.
  45. 45. Normalized Routing Load 0 2 4 6 8 10 12 14 16 18 20 15 45 75 105 135 Number of sources Normalizedroutingload DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 45 Normalized routing load as a function of Traffic sources in low and high mobility scenarios.
  46. 46. Control Overhead 0 2 4 6 8 10 12 14 15 45 75 105 135 Millions Number of sources Controloverhead(bytes) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 20 40 60 80 100 120 140 160 180 200 15 45 75 105 135 Thousands Number of sources Controloverhead(packets) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 46 Control Overhead load as a function of Traffic sources in low and high mobility scenarios.
  47. 47. Influence of node density 47 In this section the results of the simulations carried out by varying the number of nodes over the network area from 30 to 150 with two different pause times are presented separately with 30% and 70% of the nodes forming the traffic.
  48. 48. Packet Delivery Fraction 0 20 40 60 80 100 120 30 60 90 120 150 Number of nodes per sq. km Packetdeliveryfraction(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 10 20 30 40 50 60 70 80 30 60 90 120 150 Number of nodes per sq. km Packetdeliveryfraction(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 48 (a) 30% sources (b) 70% sources Packet delivery fraction as a function of number of nodes per sq. km. and 30%, 70% traffic sources.
  49. 49. Channel Utilization 0 2 4 6 8 10 12 14 16 30 60 90 120 150 Number of nodes per sq. km Channelutilization(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 2 4 6 8 10 12 14 16 18 20 30 60 90 120 150 Number of nodes per sq. km Channelutilization(%) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 49 (a) 30% sources (b) 70% sources Channel utilization as a function of number of nodes per sq. km. and 30%, 70% traffic sources.
  50. 50. Average End To End Delay 0 0.5 1 1.5 2 2.5 3 3.5 4 30 60 90 120 150 Number of nodes per sq. km Averageendtoenddelay(sec) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 1 2 3 4 5 6 7 8 9 30 60 90 120 150 Number of nodes per sq. km Averageendtoenddelay(sec) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 50 (a) 30% sources (b) 70% sources Average end to end delay as a function of number of nodes per sq. km. and 30%, 70% traffic sources.
  51. 51. Normalized Routing Load 0 1 2 3 4 5 6 7 8 30 60 90 120 150 Number of nodes per sq. km Normalizedroutingload DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 2 4 6 8 10 12 14 16 18 20 30 60 90 120 150 Number of nodes per sq. km Normalizedroutingload DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 51 (a) 30% sources (b) 70% sources Normalized routing load as a function of number of nodes per sq. km. and 30%, 70% traffic sources.
  52. 52. Control Overhead 0 10 20 30 40 50 60 70 80 90 30 60 90 120 150 Thousands Number of nodes per sq. km Controloverhead(packets) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 20 40 60 80 100 120 140 160 180 30 60 90 120 150 Thousands Number of nodes per sq. km Controloverhead(packets) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 1 2 3 4 5 6 7 30 60 90 120 150 Millions Number of nodes per sq. km Controloverhead(bytes) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 0 2 4 6 8 10 12 14 30 60 90 120 150 Millions Number of nodes per sq. kmControloverhead(bytes) DSR, p = 0s CBRP, p = 0s DSR, p = 300s CBRP, p = 300s 52 (a) 30% sources (b) 70% sources Control Overhead as a function of number of nodes per sq. km. and 30%, 70% traffic sources.
  53. 53. Conclusions 53 DSR has a lower PDF than CBRP in high mobility (0s pause time) scenarios and more or less same PDF in stationary (300s pause time) scenarios. In high mobility scenarios, the PDF due to 30% traffic sources is better than that due to 70% traffic sources. The performance degradation in PDF is due to packet drops by the routing algorithm after being failed to transfer data in the active routes. The packet drops are due to network partitioning, link break, collision and congestion in the ad hoc network.
  54. 54. 54  CBRP has lower NRL than DSR in high mobility (0s pause time) and a higher NRL in case of stationary (300s pause time) scenarios. This is because CBRP only broadcasts route requests to cluster heads. Gateway nodes receive the route requests as well but they forward them to the next cluster-heads. This largely reduces the route discovery packets which in turn reduces NRL. CBRP has a better throughput than DSR in high mobility and stationary scenarios with both traffic sources. This better throughput comes from its cluster based structure which largely reduces network traffic. For more information on network simulators and simulations www.nshubforum.com nshubforum@gmail.com , info@nshubforum.com

×