DSR The Dynamic Source Routing Protocol

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DSRThe Dynamic Source Routing Protocol

• Students
• Mirko Gilioli
• Mohammed El Allali

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Introduction

• DSR is designed for MANETs
• DSR doesnt need any network infrastructures
• Loop free routing
• No routing information in the intermediate nodes
• Nodes may easily cache this routing information
  for future use

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Assumption for the simulation

• All nodes in the MANETs are willing to
  partecipate fully in the DSR protocol.
• The diameter of the MANET will often be small (5
  to 10 hops).
• The speed with which node moves, is moderate with
  respect to the packet transmission latency.
• Nodes may be able to enable promiscuous receive
  mode on their wireless network interface.
• DSR operate with uni-directional link.
• Each node selects a single IP address.

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DSR Mechanisms

• Route discovery
• Route maintenance
• Mechanisms on-demand
• No periodic routing advertisement
• No link status sensing
• No neighbor detection packets
• Routes caching

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Basic DSR Route Discovery

• Before
• Route discovery starts

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Basic DSR Route Discovery

• Route reply message
• Piggyback
• Exponential back-off
• The node must limit the Route Discoverys rate
  until a route reply message is received
• The additional data packet sent over the limit
  should be buffered

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Basic DSR Route Maintenance

• Each node transmitting the packet is responsible
  for confirming that the packet has been received
  by next hop.
• Acknowledgement
• By lower layer protocol MAC
• By DSR-specific software ack
• Route errore message

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Additional Route Discovery features

• Caching overheard routing information
• In presence of uni-directional link
• In presence of bi-directional link

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Additional Route Discovery features

• Replying to Route Request using cached routes
• The intermediate node must verify that the
  resulting route being returned contains no
  duplicate nodes listed in the route record

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Additional Route Discovery features

• Preventing Route Reply storms
• Many Route Reply message could be send to A from
  the As neighbors
• To avoid a possible local congestion, each nodes
  must wait a variable period before sending the
  reply.
• Delay period d H(h - 1 r)
• Each node network interfaces works into
  promiscuous receive mode.

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Additional Route Discovery features

• Route request Hop limits
• Nonpropagating Route Request
• Propagating Route Request
• Expanding ring

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Support for Heterogeneous networks mobile IP

• Heteregenous network
• Different kind of devices with different
  interfaces.
• Possibly , multiple interfaces( short range
  long range)

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Support for Heterogeneous networks mobile IP

• Heteregenous network
• Different kind of devices with different
  interfaces.
• Possibly , multiple interfaces( short range
  long range)

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Source routeA/1?B/1?C/4?D/1
Reverse routeD/1?C/4?B/2?A/1
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Internet Interconnection and MIP
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DSR evaluation

• Simulation
• To analyse the behavior and performance of DSR.
• To Compare with other routing protocols
• Set Up
• Ad hoc of 50 mobiles nodes
• 15 minutes ( 900 seconds) simulation time.
• CBR data traffic
• 20 mobile nodes traffic sources 4 packets/sec.
• Random waypoint mobility model ( pause time)

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Results
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Results
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Results
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Results
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Conclusion

• Excellent performance for routing in multi-hop ad
  hoc.
• Very low routing overhead.
• Able to deliver almost all originated data
  packets, even with rapid motion of all nodes.