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| – |
redesign
of Lamport’s Mutual Exclusion Algorithm:
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n |
two-tier
structure: most of the coordination between MSS only
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n |
if MH
wants to enter critical section, it contacts local MSS
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n |
local
MSS obtains permission to enter critical section, which it
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passes
on to requesting mobile
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n |
if
requesting mobile leaves cell, update status during handoff
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(the
model provides for “leave” messages when stations
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disconnect)
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n |
result:
most communication limited to fast backbone, mobile
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stations
are allowed to disconnect and to doze off
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using
two-tier strategy is basically similar to
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“application
partitioning”
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