files/en-us/web/http/reference/headers/sec-private-state-token-crypto-version/index.md
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The HTTP Sec-Private-State-Token-Crypto-Version {{Glossary("Fetch Metadata Request Header")}} is used by the Private State Token API during token issuance to indicate to the issuer server which cryptographic protocol version should be used to sign blinded nonces when generating tokens.
At the time of writing, there is only one version supported, but this mechanism makes it possible to support multiple versions in the future.
Note that a developer wouldn't be expected to generate Sec-Private-State-Token-Crypto-Version request headers — these are created automatically by the browser when invoking private state token token-request fetch requests.
Sec-Private-State-Token-Crypto-Version: <string>
Servers should ignore this header if it contains any other value.
<string>
Sec-Private-State-Token-Crypto-Version: PrivateStateTokenV1VOPRF
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