What's your technical method to prevent users from creating fake accounts?

[reaon]

What do I mean for ''fake account''? Some users create different account for different reasons:

• Trolling
• Voting!
• They are very shy: Assume A is a professional user in your forum and now he has an elementary question! A creates another account to ask his simple question.
• etc

[baris]

NodeBB core doesn't have anything to prevent this. But plugins can be made to prevent multiple accounts from the same IP etc although it can be easily by passed.