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From: Oliver.Kowalke_at_[hidden]
Date: 2007-02-28 02:11:47

Hello Andy,

> My implementation of version 4 (random-number-based) guids
> may not be unique in space and time. It is based on
> boost::mt19937 to generate random numbers and it is seeded
> with std::time(0). Cryptographic-quality random numbers
> would reduce the probability of repeated values.
> Using version 5 (name-based) guid can be used to ensure that
> guids are unique in space (guids generated on several
> computers at the same time) and time. Generate a guid for
> each computer as the namespace_guid and pass a counter as the
> name to the create function.

Because creating uuid v5 seams too expensive for me I could let one
special computer (in my project == master) generate guids (unique in
So I've make a decision wether uuid v4 or v1 should be used in order to
be uinque in time?!
Or do you have another suggestion?


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