1 4 th International Conference on Systems and Network Communications IEEE ICSNC 2009 Porto, September 2009 Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks Emmanuel Baccelli Juan Antonio Cordero Philippe Jacquet Équipe Hipercom, INRIA Rocquencourt (France)

2 Stating the Problem OSPF over MANET Link State Flooding (LSAs) LSDB synchronization (adjacencies) Multi-Point Relaying Techniques RFC 5449 Flooding Optimization Adjacency Selection Topology Reduction Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

3 Multi-Point Relaying (MPR) Techniques Usual floodingMPR flooding multi-point relay Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

4 OSPF Legacy Principle 1 User data only forwarded over shortest paths Principle 2 User data only forwarded over LSDB- synchronized (adjacent) links Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

5 Configuration 2Configuration Elements of OSPF MANET MPR Flooding Smart Peering MPR Adj. Selection SLO-T Selection Unsynchr. Adjacencies No reduction MPR Topology Reduction Adjacency Selection Topology Reduction Flooding Optimization RFC 5449 Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

6 TWOWAY neighbors Flooding Optimization MPR Candidates/Scope: bidirectional and adjacent neighbors FULL adjacent neighbors Multi-Point Relays Selection RFC 5449 Cfs. 2.1, 2.2 Cfs. 1.1, 1.2 Relays are selected among 1-hop neighbors so that they cover all 2-hop neighbors  Size versus quality Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

7 SPT? AdjacentNon-Adjacent New 2-way neighbor Smart Peering Adjacency Selection MPR Adjacency, Smart Peering and SLO-T Reduction Link A-B adjacent if: B is MPR of A (or vice versa) MPR Adjacency Reduction SLO-T Reduction Configuration 2Configuration MPR Flooding Smart Peering MPR Adj. Selection SLO-T Selection Unsynchr. Adjacencies No reduction MPR Topology Reduction Adjacency Selection Topology Reduction Flooding Optimization RFC 5449 Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

8 Adjacency Selection Smart Peering, MPR Adjacency and SLO-T Reduction  Adjacency stability & size  Shortest paths Smart Peering MPR Adjacency Reduction SLO-T Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

9 Topology Reduction Smart Peering and MPR Topology Reduction Configuration 2Configuration MPR Flooding Smart Peering MPR Adj. Selection SLO-T Selection Unsynchr. Adjacencies No reduction MPR Topology Reduction Adjacency Selection Topology Reduction Flooding Optimization RFC 5449 Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

10 Topology Reduction Smart Peering and MPR Topology Reduction Advertized links in Router-LSAs  Advertize shortest paths ?  Synchronize shortest paths (adjacencies) ? YesNo Yes  RFC 5449 (2.1)  SP (1.2) No  SP + u.a. (1.1)  SLO-T (2.2) Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

11 Topology Reduction Smart Peering and MPR Topology Reduction Total traffic vs injected data traffic Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

12 DiscussionOSPF legacy in MANET operation Principle 1 User data only forwarded over shortest paths  Wireless metrics beyond hop-count Principle 2 User data only forwarded over LSDB- synchronized (adjacent) links  Short-life links synchronization vs. routing + RFC 5449 (cf. 2.1)  MPR Flooding  Adjacency Backup  MPR Adj. Selection  MPR Topology Red. Hybrid Configuration Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

13 Configuration 2Configuration MPR Flooding Smart Peering MPR Adj. Selection SLO-T Selection Unsynchr. Adjacencies Smart Peering MPR Topology Reduction (unsynchr. adj.) Adjacency Selection Topology Reduction Flooding Optimization Hybrid Configuration Structure MPR + SP Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

14 MPR + SP More efficient for dense networks Less vulnerable to network growth Dramatically cheaper in terms of overhead Hybrid Configuration Performance Delivery ratio vs # nodes Control overhead vs # nodes Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

15 Conclusions and Future Work  OSPF with respect to data paths  P1, Optimality* deep impact of shortest paths’ presence  P2, Synchronization weak effect (in MANET scenarios)  Two MPR-based extensions for MANET operation  P1+P2 RFC 5449 (conf. 2.1)  Only P1 Hybrid MPR+SP (outperforming the evaluated configurations) Future work  Refine the evaluation (real testbeds, wider simulation scopes)  Extend the MPR techniques to other IGPs (IS-IS…)  Metrics discussion Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

16 Questions? Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC

17 Backup Slides Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

18 Documentation of OSPF MANET Extensions  Simulations run over the Georgia Tech Network Simulator (GTNetS)  Implementation based on the Quagga/Zebra OSPFv3 daemon (ospf6d)  Extension for Configurations 1.1, 1.2  Following the IETF Internet Draft “Extensions to OSPF to Support Mobile Ad Hoc Networking” from M. Chandra and A. Roy (work in progress, draft- ietf-ospf-manet-or-02)  Implementation provided by Boeing and documented in the Boeing Technical Report D , by T. R. Henderson, P. A. Spagnolo and G. Pei  Extension for Configurations 2.1, 2.2  Following the IETF RFC 5449 “OSPF Multipoint Relay (MPR) Extension for Ad Hoc Networks” from E. Baccelli, P. Jacquet, D. Nguyen and T. Clausen  SLO-T mechanism following the INRIA Research Report n. 6148, by P. Jacquet.  Implementation provided by INRIA, publicly available in Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

19 Simulation Environment General Simulation Parameters  20 samples/experiment  Data traffic pattern  Constant Bit Rate UDP flow  Packet size:1472 bytes  Packet rate: 85 pkts/sec  Scenario  Square grid  Grid size: 400x400 m  Wireless α: 0,5  Node configuration  Radio range:150 m  MAC protocol:IEEE b  Node mobility  Random waypoint model  Pause: 40 sec  Speed: [0, v mx ] v mx = 0, 5, 10, 15 m/s (uniform) Performed Experiments  Fixed size grid  Constant density  Data traffic sweep  Link quality (α) sweep OSPF Configuration  Standard Parameters  HelloInterval: 2 sec  DeadInterval: 6 sec  RxmtInterval: 5 sec  MinLSInterval: 5 sec  MinLSArrival: 1 sec  Confs. 1.1, 1.2  AckInterval:1,8 sec  PushbackInterval:2 sec  Confs. 2.1, 2.2  AckInterval:1,8 sec Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

20 The α parameter Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

21 The SLO-T Algorithm Relative Neighbor Graph (RNG) AB C1 C2 C3 Synchronized Link Overlay, Triangle elimination AB C SLO-T (unit cost) Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

22 Other Pictures (1): General Parameters Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

23 Other Pictures (2): Control & Data Traffic Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009

24 Other Pictures (3): Adjacency Characterization Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009