Minimum Latency Broadcasting in Multiradio , Multichannel, Multirate Wireless Meshes
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Transcript of Minimum Latency Broadcasting in Multiradio , Multichannel, Multirate Wireless Meshes
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Minimum Latency Broadcasting in Multiradio, Multichannel, Multirate
Wireless Meshes
Junaid Qadir*, Chun Tung Chou+, Archan Misra++, and Joo Ghee Lim+
* National University of Sciences and Technology, Islamabad, Pakistan.+University of New South Wales, Sydney, Australia
++Applied Research, Telcordia Technologies,
IEEE/ACM TRANSACTIONS ON MOBILE COMPUTING, VOL. 8, NO. 11, NOVEMBER 2009
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Outline
Introduction Network and interference model Heuristics to construct MLB tree in MR2-MC
multi-rate mesh Simulation Conclusions
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Introduction
A wireless mesh network is a multihop wireless network consisting of A large number of wireless nodes Some gateway nodes and connected with a wired
network. However, low spatial reuse of a single radio
channel (due to wireless interference) poses an impediment to the widespread adoption of WMN as a viable access technology.
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Introduction
The minimum latency broadcasting (MLB) problem is particularly challenging in Multi-Radio, Multi-Hop Wireless Mesh Networks
How to support “efficient” broadcast in such networks is an important issue.
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Network and interference model
The system has C non overlapping orthogonal frequency channels Each node is equipped with Q radio interfaces
where Q <= C. In order to efficiently utilize the network
resources, two radio interfaces at the same node are not tuned to the same channel.
The channel assignment is done by the following channel assignment algorithms CCA, VCA and ISNTC
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Network and interference model
A graph ,where l and A denote the latency of each link and the channel assignment function, respectively.
vu 23 1 3
A(u)={2,3} A(v)={1,3}
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Network and interference model
Each edge is represented by a ,where
vuChannel k
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Network and interference model
A(y)={2,3}
l(w, x, 1)=l(w, x, 2)=l(y, z, 3)= 1/5.5
300 m
l(w, z, 1)=l(x, y, 2)=1
400 m
latency
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Network and interference model
Link-layer multicast transmissions 4-tuple : the node p V is to transmit to all
the nodes in the set I V in a link-layer multicast using latency l on channel k.
For , the following are required
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Problem statement
Given the graph , and the broadcast source node s, the objective is to find a set of link-layer multicast transmissions such that: The union of all links from all the transmissions
forms a spanning tree on G The broadcast latency is minimized
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Heuristics to construct MLB tree in MR2-MC multi-rate mesh
Multiradio, Multichannel Shortest Path Tree (MSPT)
Multi-radio, Multichannel WCDS Tree (MWT) Locally Parallelized, Multi-radio, Multichannel
WCDS Tree (LMT) Parallelized, Approximate-Shortest, Multi-
radio, Multichannel WCDS Tree (PAMT)
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Multiradio, Multichannel Shortest Path Tree (MSPT)
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Multiradio, Multichannel Shortest Path Tree (MSPT)
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Multiradio, Multichannel Shortest Path Tree (MSPT)
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Multi-radio, Multichannel WCDS Tree (MWT)
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Multi-radio, Multichannel WCDS Tree (MWT)
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Multi-radio, Multichannel WCDS Tree (MWT)
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Locally Parallelized, Multi-radio, Multichannel WCDS Tree (LMT)
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Locally Parallelized, Multi-radio, Multichannel WCDS Tree (LMT)
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Channel 2|{B,C}| / 1 = 2Channel 3
|{A, B,C}-{B,C}| / 3 =0
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Parallelized, Approximate-Shortest, Multi-radio, Multichannel WCDS Tree (PAMT)
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Label=1=latency
Label=2
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N(A,2,1)={B,C,D} N(A,2,1)={B,C}
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Simulation
N nodes are randomly located in an area of 1200m * 1200 m
three channel assignment schemes in our current work: CCA, VCA, and INSTC
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CCA
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fixed random
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Simulation
INSTC—construct a K-connected graph
1-connected topology
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VCA, INSTC > CCA
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Simulation
CCA channel assignment100 packets
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Conclusions
The authors proposed four heuristic algorithm for MR2-MC WMNs
PAMT outperforms the other algorithms The performance of CCA (which usually
performs poorly for unicast flows) is generally better than both VCA and INSTC.
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Thank you~
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MSPT
LMT PAMT
MWT