A Preferred Link Based Multicast
Protocol for Wireless Mobile Ad
hoc Networks
R. S. Sisodia, Karthigeyan. I, B. S. Manoj,
and
C. Siva Ram Murthy
ICC 2003
Outline
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Introduction
Multicast Tree
Preferred Link Based Algorithm
Tree Maintenance
Performance
Conclusions
Introduction
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Existing multicast routing protocols can
be broadly classified into two categories
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Tree based protocols
Mesh based protocol
Mesh based protocols have high packet
delivery ratio compared to tree based
protocols
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More control overhead
JoinQuery packets
Introduction (cont.)
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This paper propose an efficient
protocol
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Preferred Link Based Multicast protocol
(PLBM)
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Uses a preferred link approach for
forwarding JoinQuery packets
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Preferred link based algorithm
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Restricts the flooding of JQ packets
Preferred nodes
Locally repairs broken links
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The local two hop network topology
Multicast Tree
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Tree nodes
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Multicast source
Connected member nodes
Forwarding nodes
Neighbors Neighbors Table (NNT)
Connect Table (CT)
Multicast Tree (cont.)
Preferred Link Based Algorithm
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The PLBA
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Preferred links (nodes)
Utilizes the two hop topology
information
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NNT
E
C
B
Preferred node
D
A
Preferred Link Based Algorithm (cont.)
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Condition 1
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The current forwarding node excludes
all its neighbors that have already
forwarded JQ
D
E
B
C
JQ
A
Preferred Link Based Algorithm (cont.)
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Condition 2
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The current forwarding node is
prevented from forwarding JQ to those
neighbors that are shared by the nodes
D
B
C
A
Preferred Link Based Algorithm (cont.)
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Condition 3
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Prevents broadcast to those nodes that
are neighbors of nodes in the traversed
path of JQ
D
B
D
C
A
Preferred Link Based Algorithm (cont.)
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Example
Preferred Link Based Algorithm (cont.)
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Example
Tree Maintenance
PACKET_AWAIT_TIMER
Performance
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GloMoSim
Simulation Area 1000X1000 m
The simulation is run for 600
seconds
Transmission Rage 250m
Nodes 50
PACKET_AWAIT_TIMER 1 sec
Performance (cont.)
Group size 20
Performance (cont.)
Mobility 9 m/s
Conclusions
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An efficient receiver-initiated tree
based multicast protocol
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Preferred link based approach
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Dominating set