HTTP 407 Proxy Authentication Required

Overview

The HTTP 407 Proxy Authentication Required status code indicates that the client must first authenticate itself with the proxy. It’s similar to 401 Unauthorized but specifically used for proxy servers.

Purpose

The HTTP 407 response is used in proxy server environments, informing the client that it must authenticate with the proxy before the request can proceed.

Usage

Client Behavior:

1. Send Request: The client sends an HTTP request through a proxy server.
2. Receive Response: The client receives the HTTP 407 status code, indicating the need for proxy authentication.

Server Behavior:

1. Proxy Authentication: The proxy server determines that authentication is required.
2. Send Response: The proxy server sends a 407 Proxy Authentication Required response, typically with a Proxy-Authenticate header specifying how to authenticate.

Scenarios

• Proxy Server Environments: In network environments where proxy servers are used for internet access.
• Authentication for Secure Proxies: When proxy servers require users to authenticate for security reasons.

Sequence Diagram

Illustrating the process for an HTTP 407 response:

sequenceDiagram
    participant Client
    participant Proxy as Proxy Server

    Note over Client: Client sends a request through a proxy
    Client->>Proxy: GET http://example.com/resource HTTP/1.1
    Note over Proxy: Proxy requires authentication
    Proxy->>Client: HTTP/1.1 407 Proxy Authentication Required
    Proxy->>Client: Proxy-Authenticate: Basic realm="Proxy"

Curl Request and Response Example

Sending a request through a proxy requiring authentication using Curl:

curl -i -x http://proxy.example.com:8080 http://example.com/resource
# Expected response: HTTP/1.1 407 Proxy Authentication Required
# Proxy-Authenticate: Basic realm="Proxy"

PHP cURL Request and Response Example

PHP script using cURL to handle a 407 Proxy Authentication Required response:

<?php
$ch = curl_init('http://example.com/resource');
curl_setopt($ch, CURLOPT_PROXY, 'http://proxy.example.com:8080');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);
if (curl_getinfo($ch, CURLINFO_HTTP_CODE) == 407) {
    echo "Proxy authentication required.";
}
curl_close($ch);
?>

Python Request and Response Example

Python script to send a request through a proxy requiring authentication, handling a 407 response:

import requests
proxies = {'http': 'http://proxy.example.com:8080'}
response = requests.get('http://example.com/resource', proxies=proxies)
if response.status_code == 407:
    print("Proxy authentication required")

Apache Configuration for HTTP 407 Proxy Authentication Required

Configuring Apache as a forward proxy requiring authentication:

# Note: Apache configuration as a forward proxy is complex and beyond
# the scope of this Markdown content. Refer to Apache's documentation for details.

NGINX Configuration for HTTP 407 Proxy Authentication Required

Setting up NGINX as a forward proxy requiring authentication:

# Note: NGINX does not natively act as a forward proxy. Third-party modules or
# specific configurations are needed for this functionality.

HTTP 406 Not Acceptable HTTP 408 Request Timeout