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Reactive Routing Protocols for Ad hoc Mobile Wireless Networks

Reactive Routing Protocols for Ad hoc Mobile Wireless Networks. Wireless Network Seminar Emad Felemban. Overview. Ad Hoc Routing Protocols. Reactive. Proactive. Demand-Driven . Table-Driven. WRP. DSDV. AODV. LMR. DSR. ABR. CGSR. SSR. TORA.

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Reactive Routing Protocols for Ad hoc Mobile Wireless Networks

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  1. Reactive Routing Protocols for Ad hoc Mobile Wireless Networks Wireless Network Seminar Emad Felemban

  2. Overview Ad Hoc Routing Protocols Reactive Proactive Demand-Driven Table-Driven WRP DSDV AODV LMR DSR ABR CGSR SSR TORA Elizabeth Royer and Chai Keong Toh, “A review of Current Routing Protocols for Ah Hoc Mobile Wireless Networks”, IEEE personal Communications April 1999

  3. Proactive vs Reactive

  4. On-Demand Routing Protocols Hop-by-Hop Routing Source Routing ABR DSR AODV LMR LAR RDMAR SSA TORA Elizabeth Royer and Chai Keong Toh, “A review of Current Routing Protocols for Ah Hoc Mobile Wireless Networks”, IEEE personal Communications April 1999

  5. Source Routing vs Hop-by-Hop Routing

  6. General Properties • Loop Free Routing • Two Operation Phases • Route Establishment • Route Request  RouteRequest Packet, flooded by the Source node • Route Reply  RouteReply Packet, returned to source node by Destination or Intermediate node • Route Maintenance • Route Reconstruction • Route Deletion

  7. Protocols • DSR: Dynamic Source Routing • ABR: Associativity-Based Routing • SSA: Signal Stability-Based Adaptive Routing Algorithm • AODV: Ad Hoc On-Demand Distance Vector • LAR : Location Aided Routing Protocol • RDMAR: Relative Distance Micro-Discovery Ad Hoc Routing • LMR: Light-weight Mobile Routing • TORA: Temporally Ordered Routing Algorithm • ARA: Ant-colony-based Routing Algorithm

  8. On-Demand Routing Protocols Hop-by-Hop Routing Source Routing ABR DSR AODV LMR LAR RDMAR SSA TORA Elizabeth Royer and Chai Keong Toh, “A review of Current Routing Protocols for Ah Hoc Mobile Wireless Networks”, IEEE personal Communications April 1999

  9. Dynamic Source Routing (DSR) • Full source-route is aggregated in RouteRequest, and sent back in RouteReply • Each data packet carry the full address for all nodes along the path • Can store Multiple routes to destination • Good for Small/ Low mobility networks

  10. DSR– Route Discovery • Source Node broadcast RouteRequest packet • Each Intermediate node do the following steps: • If request received before  discard • If node ID is listed in request  discard • If Route to the destination is available send RouteReply to the source node with full path • Otherwise  append node ID and rebroadcast • When destination is reached  return RouteReply with full path • Intermediate nodes cache all paths they overhear • Source node caches all paths received and choose Shortest Path

  11. DSR - Route Request S-B S-B-E E B S D S-B-C S-B C S S-A-G-F F S-B-C S A G S-A-G S-A RouteRequest Dropped

  12. DSR - Route Reply B-E-D E-D S-B-E-D S-B-E-D E B S-B-E-D D C S S-A-G-F-D F F-D S-A-G-F-D A S-A-G-F-D G A-G-F-D S-A-G-F-D G-F-D

  13. DSR– Route Maintenance • Triggered when a link breaks between two nodes along the path from the Source to the destination • Node who discover the break send a RouteError to inform the source node about the broken link • Source Node • erase the route from the cache, and • Use another cached routes, Or • Request a new Route

  14. DSR – Route Maintenance RouteError E B RouteError D C S F A G

  15. DSR • Promiscuous mode, intermediate nodes learns about routes breaks • During network partition, if the destination is in different partition a backoff algorithm is used to prevent frequent RouteRequest broadcast

  16. DSR -- Concerns • Scalability • Large overhead in each data packet • No Local repair of the broken link • Stale cache information could result to inconsistence during route reconstruction • Poor Performance as Mobility increases

  17. Associativity-Based Routing (ABR) • Select Longer-Lived routes • Beacon based protocol • Defining the Location Stability between nodes • Used as a metric instead of shortest hop • Determined by beacon counting • Links between nodes classified into Stable and Unstable link according to beacons counts

  18. ABR– Route Discovery • Source Node broadcast RouteRequest packet • Each intermediate node do the following steps: • If request received before  discard • If node ID is listed in request  discard • If route to the destination is available  send RouteReply • Otherwise  append node ID and Beacon Count and rebroadcast

  19. ABR– Route Discovery • Destination node • Once get the first RouteRequest, it waits for certain period to receive multiple RouteRequests • From multiple routes, it selects the route with maximum proportion of stable links • If more than one route has the maximum proportion of stable links, the shortest path is selected • Only single route is selected by the destination

  20. ABR - Route Request S-B S-B-E E B S D S-B C S-B-C S S-B-C-F F S-B-C S A G S-A-G RouteRequest Dropped S-A Unstable Link

  21. ABR - Route Reply E B S-B-C-F-D D C S S-B-C-F-D F A G

  22. ABR – Route Maintenance • Try to bypass the broken link without flooding the RouteRequest globally • Downstream node, sends RouteError to the destination, deleting cache entries along the path • Upstream node broadcasts a RouteRepair with limited time to live • If failed, next upstream node broadcast RouteRepair • Is successful, new route is used • If the process traverse near source node, a new RouteRequest is initiated

  23. ABR – Concerns • Chosen path may not be shortest path • May lead to higher delay in route repairs • Single path selection • High cost of periodic beaconing • Power • Bandwidth

  24. Signal Stability-based adaptive routing algorithm (SSA) • Derivative of ABR • Adds Signal Strength as a prime metric • In addition to beacon count, each node keep record of the signal strength of other neighbors • Links are classified as Strong/Stable links vs Weak/unstable links

  25. SSA– Route Discovery • RouteRequests are forwarded through strong/stable links only • RouteRequest received through weak/unstable links are dropped • Failed RouteRequest  flood route discovery without Signal strength metric • Destination node,once get the first RouteRequest over stable links, it sends RouteReply

  26. SSA - Route Request S-B S-B-C-E E B S D S-B-C S-B C S S-B-C-F F S-B-C S A G S-A-G S-A RouteRequest Dropped Unstable Link

  27. SSA - Route Reply E B D C S S-B-C-F-D F A G

  28. SSR – Route Maintenance • End nodes of the broken links notify source and destination • Erasing cache entries along the path • Source broadcast a new RouteRequest to find Stable link

  29. SSA – Concerns • Restrict condition on forwarding RouteRequest  large setup time in case no stable links are found

  30. On-Demand Routing Protocols Hop-by-Hop Routing Source Routing ABR DSR AODV LMR LAR RDMAR SSA TORA Elizabeth Royer and Chai Keong Toh, “A review of Current Routing Protocols for Ah Hoc Mobile Wireless Networks”, IEEE personal Communications April 1999

  31. Ad Hoc On-Demand Distance Vector Routing (AODV) • Source Routing (DSR, ABR and SSA) is good for smaller networks due to large data packet overhead • AODV: • Hop by Hop basis • No need to include the full path in the data packet • Update Neighborhood information through periodic beacons

  32. AODV– Route Discovery • Source Node broadcast RouteRequest packet • Each intermediate node gets a RouteRequest do the following steps: • Establish a reverse link to node it received the RouteRequest from • If request received before  discard • If route to destination is available and up-to-date  return RouteReply using the reverse link • Otherwise  rebroadcast the RouteRequest • Destination node respond with RouteReply using the reverse link

  33. AODV - Route Discovery E B D C S F A G RouteRequest

  34. AODV - Route Discovery E B D C S F A G Reverse Path Setup RouteRequest

  35. AODV - Route Discovery E B D C S F A G RouteRequest Dropped Reverse Path Setup RouteRequest

  36. AODV - Route Discovery E B D C S F A G RouteReply Reverse Path Setup RouteRequest

  37. AODV - Route Discovery E B D C S F A G Forward Route Setup RouteReply Reverse Path Setup

  38. AODV - Route Discovery E B D C S F A G Forward Route Setup RouteReply Reverse Path Setup

  39. AODV - Route Discovery E B D C S F A G Forward Route Setup RouteReply Reverse Path Setup

  40. AODV – Route Maintenance • When a node detects a link failure, it sends special RouteReply with infinity distance • RouteReply is propagated to source node • Source node initiates a new RouteRequest

  41. AODV – Route Maintenance RouteReply E B RouteReply D C S F A G

  42. AODV Concerns • Route Reply from intermediate nodes can lead to inconstant routes  Stale Cache • Periodic beaconing cost

  43. Location Aided Routing (LAR) • Reduce the routing overhead in the network • Source node flood the request to certain area where it last heard from the destination • For the first time, it uses normal flood mechanism broadcast to all locations • GPS is required

  44. LAR • Expected Zone: The region that may contain the destination based on its previous location, speed and time. • Request Zone: The region that RouteRequest packet are allowed to propagate to reach the destination

  45. LAR • Two Scheme: • Flood the RouteRequest into the request zone only to reach the destination in the expected zone • Stores the coordinates in the route request packets, the packets can only travel in the direction where the relative distance to the destination becomes smaller

  46. LAR • Destination: once receive RouteRequest from the source, it sends RouteReply with its location and time stamp

  47. Relative Distance Micro-Discovery ad hoc routing(RDMAR) • Reduce the routing overhead in the network • Minimize the flooding effect by limiting route request to certain number of hops • Used in Route Construction and Maintenance • No need for GPS • At the first time it works like normal flooding operation Route discovery will have global effect

  48. Light Wight Mobile Routing (LMR) • Destination rooted Directed Acyclic Graph  Based of link reversals protocol • Multiple route to the destination • no need to initiate another RouteRequest unless all routes failed • Less Overhead • Good for routing in moderate mobile network

  49. LMR– Route Discovery • Every node is aware of its neighbors • Once RouteRequest received by one of the destinstion neighbors it sends RouteReply • As the RouteReply packet traverse back to the source node, DAG is constructed

  50. LMR - Route Request E B D C S F A G

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