Asked by: Beau Steinbrecht
technology and computing databases

What are the chances of a GUID collision?

Last Updated: 9th March, 2020

Assuming a perfect source of entropy on each devicegenerating random GUIDs, there is a 50% chance ofcollision after 2.7e18 random GUIDs have beengenerated. That's more than 2.7 million million million. That's alot.

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Furthermore, what are the chances of generating the same GUID?

The term GUID is generally used by developersworking with Microsoft technologies, while UUID is used everywhereelse. 128-bits is big enough and the generation algorithm is uniqueenough that if 1,000,000,000 GUIDs per second were generatedfor 1 year the probability of a duplicate would be only50%.

Also, what is GUID used for? A GUID (global unique identifier) is a termused by Microsoft for a number that its programminggenerates to create a unique identity for an entity such as a Worddocument. GUIDs are widely used in Microsoft productsto identify interfaces, replica sets, records, and otherobjects.

Also know, how many GUID combinations are there?

GeneratingGUID Trivia: "There are 122 random bits (128 - 2 forvariant - 4 for version) so this calculates to 2^122 or5,316,911,983,139,663,491,615,228,241,121,400,000 possiblecombinations."

Are GUIDs random?

GUIDs are designed to be unique, notrandom. The GUID generation algorithm was designedfor uniqueness. It was not designed for randomness or forunpredictability. Indeed, if you look at an earlier discussion, youcan see that so-called Algorithm 1 is non-random and totallypredictable.

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What is the difference between GUID and UUID?

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How do you pronounce GUID?

How do you pronounce "GUID?"

The frequency I've heard (in London, GB) would be:
  1. /ˈguː?d/ (two syllables)
  2. /ˈgw?d/ (one syllable; my preference)
  3. /ˌd?iː juː ˈa? diː/ (foursyllables)
  4. /ˌgu(w)?.ˈdiː/ (three syllables: gooey-dee)

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GUIDs are typically 16 Bytes and can store 3.4X10^38 unique values.

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What is permanent unique ID?

A persistent identifier (or permanentIdentifier or handle) is one that never changes, so that yourbookmarks and links don't break when a website gets updated. DOI(Digital Object Identifier) is a permanent identifierused to uniquely identify objects.

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What is a GUID in Active Directory?

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How long is a GUID?

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What does UUID stand for?

Universal Unique Identifier

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Is UUID really unique?

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The UUID is used for uniquely identifyinginformation. It identifies a particular service provided by aBluetooth device. So, an Android phone can connect toa device and then use the Service Discovery Protocol (SDP) to findout what services it provides (UUID).

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Where can I find UUID?

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Is a GUID a hash?

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What is GUID full form?

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