Which HTTP status code means the request requires authentication to proceed?

Which HTTP status code means the request requires authentication to proceed?

• A. Unauthorized - Your request requires authentication
• B. Forbidden - Access is denied
• C. Not Found - The resource does not exist
• D. Internal Server Error - Server failure

Answer: (A)

When a client tries to access a protected resource, HTTP uses status codes to tell the client what to do next with authentication and authorization. The code that signals authentication is required is the one that indicates the request needs the client to provide valid credentials before it can proceed. This is described as Unauthorized, and it corresponds to 401 Unauthorized. It directly communicates that authentication is necessary to access the resource, often accompanied by a WWW-Authenticate header that explains how to authenticate. If the client does provide valid credentials but isn’t allowed to access the resource, a different code is used to indicate that access is forbidden for the authenticated user. The other two options describe separate issues: Not Found means the resource doesn’t exist, and Internal Server Error means something went wrong on the server.

When a client tries to access a protected resource, HTTP uses status codes to tell the client what to do next with authentication and authorization. The code that signals authentication is required is the one that indicates the request needs the client to provide valid credentials before it can proceed. This is described as Unauthorized, and it corresponds to 401 Unauthorized. It directly communicates that authentication is necessary to access the resource, often accompanied by a WWW-Authenticate header that explains how to authenticate.

If the client does provide valid credentials but isn’t allowed to access the resource, a different code is used to indicate that access is forbidden for the authenticated user. The other two options describe separate issues: Not Found means the resource doesn’t exist, and Internal Server Error means something went wrong on the server.