Does the captcha have anything to do with the random number of the s key?

The client sends a connection request to the server, and the server returns to the client seed and sed, and the client stitches the password and seed together for 16 bytes, splits them into 8 bytes before and after, and XOR to get S

S performs md4 operation 1 time to get the nth password, 2 times to get the n-1st password,,, server saves the first password, that is, the one that has been calculated n times, the client connection from the second password, that is, the one that has been calculated n-1 times, the client sends the password to the server, the server will perform a md4 operation on the password, if the result is the same as the password you save, let the client log in, and save the password sent by the client for the next use, record it in the log, Used for the next comparison login.

See web link.

The purpose of the captcha is to prevent some users with ulterior motives from guessing the password by brute-force cracking and other methods, because the captcha is different every time it is refreshed, and the automatic brute-force software used by those who want to brute-force it is useless. There have also been hackers who have written software that automatically recognizes the verification code, but the success rate is not high, because as long as the numbers or letters of the verification code are complicated and difficult to read with the naked eye, the hacker can stand up. Therefore, CAPTCHAs are a very effective technique to prevent hacking.

Prevent malicious registrations.

Prevent attacks. To prevent unauthorized use.

Prevent malicious registration and brute-force password cracking!

Protect your account and privacy.

The verification code is mainly used to retrieve the password of the account. Generally, there is no leakage.

In order to facilitate the server side to better handle the security of your account, prevent external malicious accounts from stealing your personal information, including your password and account number!!

The function of the captcha: to effectively prevent a hacker from doing something specific.

It is mainly anti-bot, anti-bot malicious registration, or some behavior that damages the server.

Check everyone's patience and use Kailide better.

The main thing is to prevent some people from registering, irrigating, etc.

Prevent criminals from brute-force hacking of your number.

Yes,The general verification code is a 6-digit digital signature and other information,We use the Babu platform interface,Qinxu is very fast,It's also quite stable,The app has just been launched with 300,000 registrations and there is no congestion。

1.You can use the client's IP address as the key

2.It is also possible to generate a random number as a key, and when the client obtains the verification code, it returns the key and the verification code**, and the client needs to upload this key and the verification code entered by the user during verification.

Ordinary variables are automatically emptied at the end of the function, which is called memory**, so there is no need for the variable to be gone at the end of the session page load.

High interest rates, no threshold, anyone can vote, nine and a half out of ten higher than bank loan interest rates are **.

Write alphanumeric letters inside a string, then cut them into arrays (cut or not), then write random numbers, the random range is the length of the string (array), add it to a variable in a loop, and assign a value to a dom