# Request Headers

## Authentication Headers

Most requests to the Dfns API need to be authenticated, and will need to include the following additional headers:

<table><thead><tr><th width="267.36734693877554">Header</th><th>Description</th></tr></thead><tbody><tr><td><code>Authorization: Bearer &#x3C;token></code></td><td>An authentication token (see <a data-mention href="/pages/GGwAnYQzspAlNeDWMlon#get-an-authentication-token">/pages/GGwAnYQzspAlNeDWMlon#get-an-authentication-token</a>)</td></tr></tbody></table>

## User Action Signature Header

Most requests that change the state within the Dfns system (non-GET requests basically) need to be signed (see [User Action Signing](/d/api-docs/authentication/user-action-signing.md)) by the user's credential, and require the following additional header:

<table><thead><tr><th width="289">Header</th><th>Description</th></tr></thead><tbody><tr><td><code>X-DFNS-USERACTION: &#x3C;user-action-signature></code></td><td>A one time token you got after the <a data-mention href="/pages/sagQEZmerbaXyYZDD34w">/pages/sagQEZmerbaXyYZDD34w</a> flow</td></tr></tbody></table>

## Registration Headers

Similar to authenticated endpoints, the `Complete User Registration` endpoint needs an authentication token. This token is passed in the `Authentication` header:

<table><thead><tr><th width="267.36734693877554">Header</th><th>Description</th></tr></thead><tbody><tr><td><code>Authorization: Bearer &#x3C;token></code></td><td>The temporary authentication token returned from <a data-mention href="/pages/n36P9BYdelYNu8kM5Qau#responses">/pages/n36P9BYdelYNu8kM5Qau#responses</a></td></tr></tbody></table>


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