In Zendesk they use JWT to authenticate users. I send a name, email and organisation to zendesk and Zendesk then registers the user (if not yet existing) and sends me a JWT token. Zendesk accepts all my input and just creates an account with that information.
After receiving the token I can redirect my users to go to Zendesk, login and view the knowledgebase and enter tickets.
It would be awesome if this would also be possible with Featureupvote!