What is the use of verification code?

CAPTCHA is "Completely Automated Public Turing test to tell Computers and Humans Apart" The abbreviation of "Fully Automated Turing Test to Tell Computers and Humans" is a public, fully automated program that distinguishes whether a user is a computer or a human.

Function of verification code:

1. Prevent ticket brushing, forum flooding, and page brushing

2. Prevent hackers from maliciously cracking passwords and stealing user data

Verification codes usually use some lines and some irregular characters. The main function is to prevent some hackers from Password digitization theft.

Effectively prevents a hacker from constantly trying to log in to a specific registered user using a specific program to brute force. In fact, using verification codes is a common method on many websites now (such as China Merchants Bank’s online personal banking, Baidu Community), we implemented this function in a relatively simple way. Although logging in is a little more troublesome, this function is still necessary and important for the password security of netizens.

2. Prevent malicious registration and login

Verification codes are generally used to prevent batch registration, which is difficult for the human eye, let alone a machine. Almost all formal forums require you to enter a verification code when registering. This is to prevent people who spam advertisements from using registration machines to register maliciously.

Type of verification code

● Gif animated verification code

Streaming verification code provides static pictures , it is easier to be recognized by OCR software. Some websites provide dynamic GIF verification code pictures, making it difficult for the recognizer to identify which layer is the real verification code picture. It can provide clear pictures while preventing identification more effectively. According to statistics, the anti-spam injection of animated gif verification code can reach 100%, which is a very effective verification code innovation model. At the same time, there can be up to hundreds of gif animation effects, which can also increase the beauty of the website page.

● Mobile phone SMS verification code

The mobile phone verification code is sent to the mobile phone. Large websites, especially shopping websites, all provide mobile phone SMS verification code functions, which can be more accurate and secure. It is the most effective verification code system to ensure the security of shopping and verify the correctness of users. Some verification code access providers provide SMS verification code services. Each website sends a request to the access provider's server through the interface. The server sends random numbers or letters to the mobile phone, and the access provider's server performs unified verification of the verification code.

● Mobile phone voice verification code

● Video verification code

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