How Random is System.Guid.NewGuid()?

.net random guid
GateKiller picture GateKiller · Jan 21, 2009 · Viewed 35.9k times · Source

I know this may sounds like a pointless question, but hear me out...

I basically want to know if I can trust the GUID to generate a value which will be unique 100% of the time and impossible to predict.

I'm basically rolling my on login system for a website and want to know if the GUID is secure enough for session cookies.

Any background on how the GUID is generated would be much appreciated in evaluating the answers.

Thanks for the links to duplicate questions, however, my question is specific to the .Net framework.

Answer

John Sheehan picture John Sheehan · Jan 21, 2009

Here's an excellent breakdown by Raymond Chen

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