# IdentityAttributeNonce

> **IdentityAttributeNonce** = `Uint8Array` \| `Promise`\<`Uint8Array`\> \| (() => `Uint8Array` \| `Promise`\<`Uint8Array`\>)

Defined in: [react/src/auth/types.ts:18](https://github.com/B3Pay/ic-reactor/blob/70bedf3c8779611a3b35710510442dee7f630b87/packages/react/src/auth/types.ts#L18)

The 32-byte nonce issued by the relying-party canister.

A function (or promise) lets the Internet Identity window open while the
nonce is still being fetched, so the popup is opened inside the user gesture
instead of after it. Every supported `@icp-sdk/auth` requires the function form, and
IC Reactor normalizes whichever of these you pass into that thunk.