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| n |
THE
big problem of distributed, loosely coupled systems
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are
all views on data the same?
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how
and when should changes be propagated to what users?
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| n |
Weak
consistency
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– |
many
algorithms offering strong consistency (e.g., via atomic
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updates)
cannot be used in mobile environments
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invalidation
of data located in caches through a server is very
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problematic
if the mobile computer is currently not connected to
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the
network
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occasional
inconsistencies have to be tolerated, but conflict
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resolution
strategies must be applied afterwards to reach
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consistency
again
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| n |
Conflict
detection
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content
independent: version numbering, time-stamps
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content
dependent: dependency graphs
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