uuid - How unique are the ids generated with CFUUID , in iOS? -


the title question actually. apple doesnt allow more use of uuid decided go cfuuid.

however have questions regarding it.

is unique every device? if yes how different uuid?

is random generator? if yes how it? can sure in 10000 devices there wont duplicate?

i between in solution of using cfuuid , , having server generating random unique identifier can sure of. need unnecessary coding , http requests between server , devices.

any ideas?

when apple doesn't allow use of uuid, must referring udid, or unique device id.

a uuid unique every time generate one. it's not udid. uuids unique globally.

is unique every device? if yes how different udid?

yes, it's unique every device because part of uuid devide id, though it's not entire udid. udid same. each time create uuid, it's different last, need store uuid if wanted use device id.

is random generator? if yes how it? can sure in 10000 devices there wont duplicate?

a uuid computed, not randomly generated. first part form of device id, , second part derived date , time. while date , time part of uuid may duplicated between devices, device id portion still guarantees unique uuids globally.


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