doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 1 Routing Protocols for MANET Avinash Joshi, Vann Hasty, MeshNetworks Inc. Michael Bahr, Siemens Corporate Technology

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 2 Overview Introduction Different Routing Protocols –Reactive Routing Protocols –Proactive Routing Protocols –Hybrid Routing Protocols IETF MANET Group Other Active work s and MANET Conclusion

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 3 Introduction Mobile Ad hoc Network (MANET) Collection of wireless mobile nodes Without using a pre-existing infrastructure Routes between nodes may potentially contain multiple hops This presentation Considers only routing protocols discussed in IETF MANET working group

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 4 Typical Ad hoc Network A E C H F I D B J G Node Transmission Range

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 5 Different Routing Protocols Proactive Routing Protocols Reactive Routing Protocols Hybrid Routing Protocols

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 6 Proactive Routing Protocols Main features: –Maintain routing information on all nodes in the network at all times. This can be achieved by event driven routing information distribution and regular distribution of updated routing information. Advantages: –Lower route setup latency Disadvantages: –High routing overhead (periodic distribution of routing information) –Stale routing information in highly dynamic topologies. Protocol examples: –Optimized Link State Routing (OLSR) –Topology Dissemination Based on Reverse Path Forwarding (TBRPF)

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 7 Reactive Routing Protocols Main features: –maintain routing information for the nodes which are needed and only for the time when they are needed (Also called on-demand routing protocols.) Advantages: –Lower routing overhead Disadvantages: –Larger route set up latency –Route discovery packet flooding Protocol examples: –Dynamic Source Routing (DSR) –Ad hoc On-demand Distance Vector (AODV)

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 8 Hybrid Routing Protocols Main features: –The routing is proactive for short distances and reactive for long distances. Advantages: –Reduces impact of disadvantages of proactive and reactive routing protocols –No route setup latency for short distance connections –Lower routing overhead due to reactive routing for further away destinations Disadvantages: –More complex Protocol examples: –Zone Routing Protocol (ZRP)

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 9 IETF MANET Working Group Description: To standardize IP routing protocol functionality suitable for wireless routing application within both static and dynamic topoligies In the past, focused on exploring a broad range of MANET problems, performance issues, and related candidate protocols Promotion of a number of core routing protocol specifications to EXPERIMENTAL RFC status

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 10 IETF MANET Working Group Current Status: Reached all milestones 3 Experimental RFCs (AODV – RFC 3561, OLSR – RFC 3626, TBRPF – RFC 3684) DSR submitted as Experimental RFC Recharter in November –decide on single reactive routing protocol and on single proactive routing protocol –aspects of security and congestion control in the designed routing protocol/protocols. OSPF-MANET in OSPF working group

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 11 Example of a Proactive Routing Protocol Optimized Link State Routing (OLSR) Experimental RFC 3626 Authors: Thomas Clausen, Philippe Jacquet, et al, Project Hipercom, INRIA (France)

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 12 OLSR Optimization of pure link state protocol –Reduced size of control packets (Only links to multipoint relay selector nodes are advertised) –Minimized flooding (only multipoint relay (MPR) nodes forward the packets)

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 13 MPR Selection Reference Node One Hop Neighbors Two Hop Neighbors

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 14 MPR Selection Selected MPRs

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 15 MPR Selection MPR can reach all the two hop neighborhood

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 16 MPR Selection MPR can reach all the two hop neighborhood

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 17 OLSR Neighbor Sensing Periodic Hello messages detect the 2- hop neighborhood A E C H F I D B J G

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 18 Multi Point Relay Selection MPR nodes are selected A E C H F I D B J G K reference node 1-hop neighbors Multi Point Relays 2-hop neighbors

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 19 Multi Point Relay Selection Only Multi Point Relays (MPRs) retransmit broadcast packets from their MPR selector A E C H F I D B J G K reference node 1-hop neighbors Multi Point Relays 2-hop neighbors

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 20 Topology Info Dissemination EVERY node MPR- broadcasts its links between itself and neighbors that selected this node as MPR A E C H F I D B J G K reference node 1-hop neighbors Multi Point Relays 2-hop neighbors

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 21 Topology Info Dissemination EVERY node MPR- broadcasts its links between itself and neighbors that selected this node as MPR A E C H F I D B J G K reference node 1-hop neighbors Multi Point Relays 2-hop neighbors

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 22 Path Computation iterative shortest path algorithm using information from neighbor table and topology table A E C H F I D B J G K

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 23 Route Break compute new MPR set broadcast TC message A E C H F I D B J G K Link Break

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 24 Route Break compute new MPR set broadcast TC message compute new path A E C H F I D B J G K Link Break

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 25 Example of a Reactive Routing Protocol Ad hoc On-Demand Distance Vector (AODV) Experimental RFC 3561 Authors: Charles Perkins, Elizabeth Belding-Royer, Samir Das

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 26 AODV Main Functions Route Discovery Route Maintenance Uses Destination Sequence Number to avoid loops and “Counting to Infinity” problem

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 27 AODV: Route Discovery A E C H F I D B J G K

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 28 AODV: Route Discovery A E C H F I D B J G K A – Source J - Destination

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 29 AODV: Route Discovery A E C H F I D B J G K ‘A’ Broadcast a route request (RREQ) packet with Initial TTL =1 Broadcast RREQ

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 30 AODV: Route Discovery A E C H F I D B J G K Nodes receiving the RREQ sets up Reverse Routes to the source Broadcast RREQ Reverse Route

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 31 AODV: Route Discovery A E C H F I D B J G K ‘A’ times out and re-broadcast a Route Request (RREQ) packet with TTL = 2 Broadcast RREQ Reverse Route

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 32 AODV: Route Discovery A E C H F I D B J G K Other Nodes Rebroadcasts the Route Request (RREQ) packet Note: Nodes B, C and F receives RREQ Multiple times but forward it only once

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 33 AODV: Route Discovery A E C H F I D B J G K ‘A’ times out and re-broadcast a Route Request (RREQ) packet with TTL = 4 Broadcast RREQ Reverse Route

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 34 AODV: Route Discovery A E C H F I D B J G K Route Request Eventually Reaches the Destination J Broadcast RREQ Reverse Route

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 35 AODV: Route Discovery A E C H F I D B J G K Destination send route Reply (RREP) back to source using the reverse route RREP

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 36 AODV: Route Discovery A E C H F I D B J G K Node Receiving the RREP sets up a Forward Path to the Destination Route Reply Forward Path

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 37 AODV: Route Discovery A E C H F I D B J G K Node Receiving the RREP sets up a Forward Path to the Destination Route Reply Forward Path

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 38 AODV: Route Discovery A E C H F I D B J G K Node Receiving the RREP sets up a Forward Path to the Destination ‘A’ now has a route to ‘J’

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 39 AODV: Route Discovery A E C H F I D B J G K A can now use the forward route created

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 40 AODV: Route Discovery A E C H F I D B J G K

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 41 AODV: Route Discovery A E C H F I D B J G K B – Source J - Destination

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 42 AODV: Route Discovery A E C H F I D B J G K ‘B’ Broadcast a route request (RREQ) packet

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 43 AODV: Route Discovery A E C H F I D B J G K ‘A’ and ‘C’ replies RREP

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 44 AODV: Route Discovery A E C H F I D B J G K ‘B’ picks the minimum hop route (which is through C)

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 45 AODV: Route Error A E C H F I D B J G K A – Source J - Destination

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 46 AODV: Route Break A E C H F I D B J G K Data is flowing between A and J

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 47 AODV: Route Error A E C H F I D B J G K Link Break Link between E and J breaks due to RF reasons, or movement

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 48 AODV: Route Error A E C H F I D B J G K Link Break All nodes maintain a precursor list of nodes who might use a link

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 49 AODV: Route Error A E C H F I D B J G K Link Break Route Error message is sent to the source

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 50 AODV: Route Error A E C H F I D B J G K Link Break Route to J is removed and Route Discovery is reinitiated

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 51 IRTF RRG Ad hoc Network Systems Research Subgroup Study of Ad hoc Network Systems (ANS) Inter-layer Protocol Interaction, Quality of Service Routing, Routing Scalability, Network Auto-Configuration, Interoperation with a wired infrastructure Currently not very active

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 52 Difference between IEEE s and IETF MANET IETF MANET Layer3 Distributed Architecture Hop Based Metrics No QoS No Security Standard No Multicast Standard Mobility? Up to Large Scale s Layer 2 Presence of Gateways LQ/Hop Based Metrics QoS Security Multicast Mobility? Reduced Scale

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 53 Current Research Link Quality (MIT) Integration of MANETs into existing Internet (several Internet drafts, EU project “Daidalos”) Security Energy-awareness

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 54 Conclusion Many general insights into routing/path finding Many concepts available, each with its advantages and disadvantages Concepts and experiences from MANETs can be used for TGs

doc.: IEEE /1047r0 Submission Month 2000August 2004 Avinash Joshi, Vann Hasty, Michael Bahr.Slide 55 References Ad Hoc Networking by Charles E. Perkins Google