Collaborate Disseminate
The Problem
In our system users are identified by a composite key. We’d like to devise a scheme to deterministically convert this composite key into a UUID.
Solutions?
The obvious first suggestion would be UUIDv5, however:
It’s based … Continue reading How to reasonably hash a composite key into a UUID?
I’d like to use a V4 UUID / GUID for authenticating users. To be specific, the user would have to paste the UUID into a text field to gain access to their account. The UUID would be given to them at the time of registration.
The UUID woul… Continue reading Using V4 UUID for authentication
Vulnerabilities in UberCENTRAL, a portal used by businesses to facilitate rides, could have leaked the names, phone numbers, email addresses, and unique IDs. Continue reading Uber Portal Leaked Names, Phone Numbers, Email Addresses, Unique Identifiers
I’m very curious as to why the format is xxxxxxxx-xxxx-4xxx-zxxx-xxxxxxxxxxxx? Why is the 4 there, and why is z always either 8, 9, A, B? And also, why the different string lengths between the dashes? What is the rationale be… Continue reading Why does UUID v4 have the format xxxxxxxx-xxxx-4xxx-zxxx-xxxxxxxxxxxx? [closed]
I’ve been reading up on GUIDs. According to the Wiki:
Cryptanalysis of the WinAPI GUID generator shows that, since the sequence of V4 GUIDs is pseudo-random, given full knowledge of the internal state, it is possible to p… Continue reading With a very large number of GUIDs, can one predict the previous and subsequent GUIDs that will be generated?