511 Network Authentication Required

Usage

The 511 Network Authentication Required status code informs the HTTP client to log in before being granted access to the network. An example of a captive portal is a hotel portal granting guests access to non-public Wi-Fi services.

The 511 Network Authentication Required status code signals to HTTP clients the response is not coming from the origin server but from a network gatekeeper requiring Authentication.

Example

The HTTP client requests a resource and the server responds with a 511 Network Authentication Required status code because the client must first authenticate before being granted regular network access.

Request

GET / HTTP/1.1
Host: example.com

Response

HTTP/1.1 511 Network Authentication Required
Content-Type: text/html; charset=UTF-8
Content-Length: 218

<html>
  <head>
    <title>Network Authentication Required</title>
  </head>
  <body>
    <p>Before accessing this service,
    <a href="https://login.example.re/">sign in
    </a> to the network.</p>
  </body>
</html>

How to fix

The network requires Authentication before granting internet access. A captive portal is intercepting HTTP traffic and returning 511 until login is complete.

For end users:

For automated clients and applications:

For network operators serving 511:

Code references

.NET

HttpStatusCode.NetworkAuthenticationRequired

Rust

http::StatusCode::NETWORK_AUTHENTICATION_REQUIRED

Rails

:network_authentication_required

http.StatusNetworkAuthenticationRequired

Symfony

Response::HTTP_NETWORK_AUTHENTICATION_REQUIRED

Python3.5+

http.HTTPStatus.NETWORK_AUTHENTICATION_REQUIRED

Apache HttpComponents Core

org.apache.hc.core5.http.HttpStatus.SC_NETWORK_AUTHENTICATION_REQUIRED

Angular

@angular/common/http/HttpStatusCode.NetworkAuthenticationRequired