Authentication · interview question
Why does a JWT ecosystem need the kid header during key rotation?
Multiple choiceMediumchapter-17-curatedpremiumauthenticationjwt-signatures
Answer and explanation
Correct answer
D. It tells the server which signing key should be used to validate the token
Why
The kid field identifies which key signed a token so the server can validate it correctly during key rotation or when multiple active signing keys exist.
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