1 4 th International Conference on Systems and Network Communications IEEE ICSNC 2009 Porto, 20-25 September 2009 Multi-Point Relaying Techniques with

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4th International Conference on Systems and Network CommunicationsIEEE ICSNC 2009Porto, 20-25 September 2009

Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks

Emmanuel BaccelliJuan Antonio CorderoPhilippe Jacquet

Équipe Hipercom, INRIA Rocquencourt (France)

2

Stating the Problem

OSPF over MANET

Link State Flooding(LSAs)

LSDB synchronization(adjacencies)

Multi-Point Relaying TechniquesRFC 5449

Flooding Optimization

AdjacencySelection

TopologyReduction

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

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Multi-Point Relaying (MPR) Techniques

Usual flooding MPR flooding

multi-point relay


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OSPF Legacy

Principle 1

User data only forwarded over shortest paths

Principle 2

User data only forwarded over LSDB-synchronized (adjacent) links


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Configuration 2Configuration 1

2.22.11.21.1

Elements of OSPF MANET

MPR Flooding

Smart Peering MPR Adj.Selection

SLO-TSelection

Unsynchr.Adjacencies

Noreduction

MPR TopologyReduction

Adjacency Selection

Topology Reduction


RFC 5449


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TWOWAY neighbors

Flooding OptimizationMPR Candidates/Scope: bidirectional and adjacent neighbors

FULL adjacent neighbors

Multi-Point Relays

Selection

RFC 5449Cfs. 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


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SPT?

Adjacent Non-Adjacent

New 2-wayneighbor

Smart Peering

Adjacency SelectionMPR Adjacency, Smart Peering and SLO-T Reduction

Link A-B adjacent if:

B is MPR of A (or vice versa)

MPR Adjacency Reduction

13

42

37

13

42

37

SLO-T Reduction


2.22.11.21.1

MPR Flooding


SLO-TSelection


No reductio

n


Adjacency Selection

Topology Reduction


RFC 5449


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Adjacency SelectionSmart Peering, MPR Adjacency and SLO-T Reduction

Adjacency stability & size

Shortest paths

Smart Peering

MPR Adjacency Reduction

SLO-T


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Topology ReductionSmart Peering and MPR Topology Reduction


2.22.11.21.1

MPR Flooding


SLO-TSelection


No reductio

n


Adjacency Selection

Topology Reduction


RFC 5449


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Advertized links in Router-LSAs

Advertize shortest paths ?

Synchronize shortest paths (adjacencies) ?

Yes No

Yes RFC 5449 (2.1) SP (1.2)

No SP + u.a. (1.1) SLO-T (2.2)


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Path length (Fixed size grid, 30 nodes, 5 m/s)

0,0

1,0

2,0

3,0

1.2 (SP only) 2.1, 2.2 (MPRTop. Red.)

(# h

ops)


Total traffic vs injected data traffic


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Discussion OSPF 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


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2.22.11.21.1

MPR Flooding


SLO-TSelection


Smart Peering

MPR Topology Reduction (unsynchr. adj.)

Adjacency Selection

Topology Reduction


Hybrid ConfigurationStructure

MPR + SP


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MPR + SP

More efficient for dense networksLess vulnerable to network growth

Dramatically cheaper in terms of overhead

Hybrid ConfigurationPerformance

Delivery ratio vs # nodes Control overhead vs # nodes


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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


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Questions?


E-mail: [email protected]

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Backup Slides


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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 D950-10897-1, 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

www.emmanuelbaccelli.org/ospf


http://www.emmanuelbaccelli.org/ospf

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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 802.11b

Node mobility Random waypoint model Pause: 40 sec Speed: [0, vmx]

vmx= 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


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The α parameter

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0,9

1

0 30 60 90 120 150

Link length (m)

Pro

ba

bili

ty o

f s

uc

es

s (

ov

er

1)

alpha=0

alpha=0,25

alpha=0,5

alpha=0,75

alpha=1


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The SLO-T Algorithm

Relative Neighbor Graph (RNG)A B

C1

C2

C3

Synchronized Link Overlay, Triangle eliminationA B

C

SLO-T (unit cost)13

42

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Other Pictures (1): General Parameters


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Other Pictures (2): Control & Data Traffic


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Other Pictures (3): Adjacency Characterization


Documents

1 4 th International Conference on Systems and Network Communications IEEE ICSNC 2009 Porto, 20-25 September 2009 Multi-Point Relaying Techniques with