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| – |
some
consequences from model:
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n |
communication
costs are no longer uniform:
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– |
relatively
cheap to communicate between two MSS
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– |
relatively
expensive to communicate MSS-MH or MH1-MH2
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n |
mobile
hosts may disconnect (or doze off), reappear later
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n |
underlying
network structure changes all the time
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| – |
model
applied to study a well-known distributed mutual
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exclusion
algorithm (Lamport’s Algorithm):
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n |
if
original algorithm implemented directly, poor performance:
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– |
high
search costs for all MH-MH messages
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– |
all
hosts required to participate, so disconnections not allowed
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– |
data
structures need to be maintained at the mobile hosts, so high
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power
usage
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