Transcript Diapositiva 1 - Polytechnique
4 th International Conference on Systems and Network Communications IEEE ICSNC 2009 Porto, 20-25 September 2009
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks
Emmanuel Baccelli
Juan Antonio Cordero
Philippe Jacquet Équipe Hipercom, INRIA Rocquencourt (France) 1
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Stating the Problem
OSPF over MANET
Link State Flooding (LSAs) LSDB synchronization (adjacencies)
Flooding Optimization Topology Reduction Adjacency Selection
Multi-Point Relaying
Techniques
RFC 5449
2
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Multi-Point Relaying (MPR) Techniques
Usual flooding MPR flooding
multi-point relay
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Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
OSPF Legacy
Principle 1
User data only forwarded over
shortest paths
Principle 2
User data only forwarded over LSDB synchronized (
adjacent
) links 4
Elements of OSPF MANET
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Flooding Optimization Adjacency Selection Topology Reduction Configuration 1 1.1
1.2
2.1
Configuration 2 2.2
RFC 5449
MPR Flooding Smart Peering Unsynchr.
Adjacencies No reduction MPR Adj.
Selection SLO-T Selection MPR Topology Reduction 5
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Flooding Optimization MPR Candidates/Scope:
bidirectional
and
adjacent
neighbors
Relays are selected among 1-hop neighbors so that they cover all 2-hop neighbors
TWOWAY neighbors FULL adjacent neighbors Multi-Point Relays Selection RFC 5449 Cfs. 2.1, 2.2
Cfs. 1.1, 1.2
Size
versus
quality 6
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Adjacency Selection
MPR Adjacency
,
Smart Peering
and
SLO-T Reduction
Link
A
-
B
Flooding Optimization adjacent if: Adjacency Selection Configuration 1 New 2-way 1.1
1.2
2.1
Configuration 2 2.2
RFC 5449
42 MPR Flooding 13 13 SPT?
Smart Peering MPR Adj.
Selection SLO-T Selection 37
B
is
MPR
of
A
Topology Reduction (or vice versa) Adjacent Unsynchr.
Adjacencies Non-Adjacent reduction MPR Topology Reduction
SLO-T Reduction
42 37
MPR Adjacency Reduction Smart Peering
7
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Adjacency Selection
Smart Peering
,
MPR Adjacency
and
SLO-T Reduction
MPR Adjacency Reduction Adjacency stability & size Smart Peering Shortest paths SLO-T 8
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Topology Reduction
Smart Peering
and
MPR Topology Reduction
Flooding Optimization Configuration 1 1.1
1.2
2.1
Configuration 2 2.2
RFC 5449
MPR Flooding Adjacency Selection Topology Reduction Smart Peering Unsynchr.
Adjacencies No reduction MPR Adj.
Selection SLO-T Selection MPR Topology Reduction 9
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Topology Reduction
Smart Peering
and
MPR Topology Reduction
Advertized links in Router-LSAs
Synchronize
shortest paths (
adjacencies
) ?
Yes No
Advertize
shortest paths ?
Yes
RFC 5449 (2.1) SP + u.a. (1.1) SLO-T (2.2)
No
SP (1.2) 10
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Topology Reduction
Smart Peering
and
MPR Topology Reduction
Total traffic
vs
injected data traffic Path length (Fixed size grid, 30 nodes, 5 m/s) 3,0 2,0 1,0 0,0 1.2 (SP only) 2.1, 2.2 (MPR Top. Red.) 11
Discussion
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
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
+ Hybrid Configuration RFC 5449
(cf. 2.1)
MPR Flooding Adjacency Backup MPR Adj. Selection MPR Topology Red
.
12
Hybrid Configuration
Structure Flooding Optimization Adjacency Selection Topology Reduction
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Configuration 1 1.1
1.2
MPR + SP 2.1
Configuration 2 2.2
MPR Flooding Smart Peering
MPR Adj.
Selection SLO-T Selection Unsynchr.
Adjacencies
Smart Peering MPR Topology Reduction
(unsynchr. adj.) 13
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Hybrid Configuration
Performance
More efficient
for dense networks
Less vulnerable
to network growth Delivery ratio vs # nodes MPR + SP Dramatically
cheaper
in terms of
overhead
Control overhead vs # nodes 14
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
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 15
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Questions?
E-mail:
[email protected]
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Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Backup Slides
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Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
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 Technical Report D950-10897-1, by T. R. Henderson, P. A. Spagnolo and G. Pei
Boeing
and documented in the Boeing 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
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Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Simulation Environment
General Simulation Parameters
20 samples/experiment
Data traffic pattern
Constant Bit Rate UDP flow Packet size: Packet rate: 1472 bytes 85 pkts/sec
Scenario
Square grid Grid size: Wireless α: 400x400 m 0,5
Node configuration
Radio range: 150 m MAC protocol: IEEE 802.11b
Node mobility
Random waypoint model Pause: Speed: 40 sec [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: DeadInterval: RxmtInterval: MinLSInterval: MinLSArrival: 2 sec 6 sec 5 sec 5 sec 1 sec
Confs. 1.1, 1.2
AckInterval: PushbackInterval:
Confs. 2.1, 2.2
AckInterval: 1,8 sec 2 sec 1,8 sec 19
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
The α parameter
1 0,9 0,8 0,7 0,6 0,5 0,4 0,3 0,2 0,1 0 0 30 60 90
Link length (m)
120 150 alpha=0 alpha=0,25 alpha=0,5 alpha=0,75 alpha=1 20
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
The SLO-T Algorithm
Relative Neighbor Graph (RNG)
A B
C1 C3 C2
A B
Synchronized Link Overlay, Triangle elimination
C 13 42
SLO-T (unit cost)
37 21
Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Other Pictures (1): General Parameters
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Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Other Pictures (2): Control & Data Traffic
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Multi-Point Relaying Techniques with OSPF on Ad Hoc Networks, IEEE ICSNC 2009
Other Pictures (3): Adjacency Characterization
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