$token = bin2hex($token); //Print it out for example purposes. What does the rainbow and bear emoji mean? If match both then user is valid. When an app user joins a channel or logs onto the service system, the app client interacts with the app server in the following way: The app client sends a request for token to the app server. Vikash Kumar Singh is a web developer, author, speaker and founder of Phpcluster. $token = openssl_random_pseudo_bytes(16); //Convert the binary data into hexadecimal representation. In login authentication to give limited resources with session of limited duration. In terms of generating the tokens, you could use one of Laravel’s Helper Functions; str_random().. Of course you can also do a storage check to ensure the token isn't already in use, but if you use a length of 64 or larger, the chances you repeat a token are incredibly slim! openssl_random_pseudo_bytes()  function generate cryptographically secure source of pseudorandom bytes. If session is not active, collision check is omitted. In order to generate a 32 character token for access to our API we currently use: $token = md5 (uniqid (mt_rand (), true)); I have read that this method is not cryptographically secure as it's based on the system clock, and that openssl_random_pseudo_bytes would be a better solution as it would be harder to predict. To generate a cryptographically secure token in PHP, you will need to use the openssl_random_pseudo_bytes function: where("token_key", "=", $token_key)->first() instanceof User); ...should do. Generating Unique Token in C# | Generating Unique Token that Expires after 24 Hours in C# | C# Tutorial ASP.NET MVC , C# There are two possible approaches; either you create a unique value and store somewhere along with the creation time, for example in a database, or you put the creation time inside the token so that you can decode it later and see when it was created. It loops this generate/check until it gets a unique token. Definition and Usage The uniqid () function generates a unique ID based on the microtime (the current time in microseconds). ... Add the service provider to config/app.php in the providers array, or if you're using Laravel 5.5, this can be done via the automatic package discovery. Thanks for your support! * doing: *. In which case and why we use it?. In our GitHub Repository, we provide source codes and token generator demos in C++, Java, Python, PHP, Ruby, Node.js, Go, C# and other programming languages. With writing few line of script, cryptographically secured tokens generate in PHP. Then I would recommend using the Guid object, to create a new unique string for every device. A php library that generates unique token. Firstly, lets look at how we can generate a token for the user: