Transcript A combinational media access protocol for multicast

A combinational media access
protocol for multicast traffic in
single-hop WDM lans
Student : T.H Lin
Teacher : H.T Wu
Date : 7.28
Outline
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Introduction
The architecture of single-hop WDM
networks
Protocol
The combinational multicast schedule
(CMS)
Simulation Results
Conclusions
Introduction
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Using reservation-based protocol
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Partitioning multicast group
Using pre-allocation-based protocol
The architecture of single-hop
WDM networks
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The Passive Star Coupler to connect N nodes.
PSC is an N * N broadcast-and select device
interconnected through the optical fibers.
Each node contains one pair of FT-FR to
collect the status of multicast traffic,
and one pair of FT-TR to access data channel.
The architecture of single-hop
WDM networks
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The network is packet-switched with
fix-size packets and operates in a slot
mode.
The buffer at each node is assumed to
N-1 queues, one dedicated queue and
to allocate one queue for multicast
transmission.
The architecture of single-hop
WDM networks
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Collision
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The arbitration procedure can avoid.
Destination conflict
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The receiver wavelength allocation map.
Multicast Traffic
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Each multicast
packet has its
own value of M.
M>Md perform
multicast
transmission.
M<Md the packet
is treated as the
unicast packet.
Protocol
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The combinational media access
protocol combines the unicast-based
protocol and the Multicast Slot
Reservation in the FT-TR architecture.
The Unicast-Based Protocol
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Each node is assigned Ω slots per cycle
and idle for the remaining N- Ω slots.
The Multicast Slot Reservation
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IF M < Md, the MSR replicates the
packet and transmits the replicated
packets from the multicast source node
to members of the multicast group
individually.
IF M > Md, the MSR makes the
reservation of the home channel of the
multicast source node.
The Multicast Slot Reservation
Control Channel Access
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Each node transmit a control packet via
the round-robin TDMA.
The Arbitration Procedure
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The request for multicast transmission
has the higher priority to reserve the
home channel and can be issued at any
time slot.
The request for unicast transmission
has the lower priority to reserve the
channel and be issued according to the
unicast protocol.
The combinational multicast
schedule (CMS)
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After receiving the control packet, all nodes
execute the Combinational Multicast Schedule
(CMS) at each time slot.
Simulation result
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The parameters are N=50 network nodes ,
Ω= 25 wavelengths.
The buffer size of the dedicated queue per
node is 100.
|G| and S are the normal distribution with
mean of 5 nodes
The nodes in the multicast group G are
randomly chosen from the uniform
distribution [0,N-1]
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Packet generation follows the Poisson
arrival process with parameter q = 0.1.
The multicast packet with prob p and the
unicast packet with prob 1-p
Md = 0 means the separate scheduling of
unicast and multicast traffic.
Md = 100 means the scheduling of
multicast traffic as unicast traffic.
Network throughput
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The expected number of transmitted packets per
time slot.
Packet delay
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The number of time slots elapsed from the slot
entering the network to the slot leaving the
network.
Conclusions
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Md needs to be analyzed in detail to
optimize the performance of the
protocol.
Reference
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W. Y. Tseng and S. Y. Kuo, “A
Combinational Media Access Protocol
for Multicast Traffic in Single-Hop WDM
LANS,” GLOBECOM’98
W. Y. Tseng, C. C. Sue and S. Y. Kuo,
“Performance Analysis for Unicast and
Multicast Traffic in Broadcast-and-Select
WDN Networks,” 1999