The `WWW-Authenticate` header itself does not close the client connection.

Instead, it is sent by the server as part of a `401 Unauthorized` response to indicate that the client must authenticate itself to get the requested response.

Whether the connection is closed depends on other factors like the HTTP version and connection headers (`Connection: close` or `Connection: keep-alive`).

In HTTP/1.1, connections are persistent by default unless specified otherwise.

For example, a server can respond with: