Are there alternative methods or technologies that could be used to achieve the same goal of preventing multiple logins with the same key?

The issue of preventing multiple logins with the same key can be solved by implementing a session management system that tracks active sessions for each user. One way to achieve this is by storing session IDs in a database and checking against them during login to ensure that only one session is active per user. 

// Start session
session_start();

// Check if user is already logged in
if(isset($_SESSION['user_id'])) {
    // Redirect to home page or display an error message
    header("Location: home.php");
    exit;
}

// Check if user's session ID is already in the database
$session_id = session_id();
$user_id = $_POST['user_id']; // Assuming user ID is submitted via a form
// Perform a query to check if the session ID is already in the database for the user
// If session ID is found, prevent login and display an error message
// If session ID is not found, proceed with login

// Store session ID in the database after successful login
// Perform a query to insert the session ID for the user

Keywords

PHP session management cookies JWT authentication

Related Questions