Authentication method and system for CAPTCHA Turing test based on static characters

Abstract

The invention discloses an authentication method and a system for CAPTCHA Turing test based on static characters. The authentication method and the system for the CAPTCHA Turing test based on the static characters include the following steps of establishing a communication connection between a server and a client, selecting randomly a static string in a static string database stored the server in advance, segmenting the static string into single characters, then calling a character image to generate a function which converts single characters into image representation, placing the single characters represented by the image into a region formed by a circular or elliptic boundary to show as a verification code on the client so as to carry out the Turing test CAPTCHA. Utilizing the region formed by the circular or elliptic boundary to place the verification code, the method can effectively prevent the character from being segmented by conventional pixel segmentation, and thus increases the difficulty of attack. The method carries out distortion, mirror image, and increasing interference lines for characters. The method carries out the characters arrangement according to the specific semantics of the characters and increases more human participation and can guarantee the safe man-machine interaction.

Description

technical field [0001] The present invention relates to the field of network communication, in particular to an authentication method and system for performing a CAPTCHA (Completely Automated Public Turning test to tell Computers and Humans Apart, "Automated Turing Test for Distinguishing Computers and Humans") Turing Test based on static characters . Background technique [0002] Today's web applications, such as e-mail, social networking sites, blogs, e-government websites, etc., have become a necessity in our daily life. With the rapid development of the Internet, security has also become a major issue of growing concern. In order to avoid huge attacks from malicious computer programs, Moni Noar introduced the concept of "Turing Test" in 1996 to distinguish whether a computer is operated by a human or a machine. In 2002, a research team at Carnegie Mellon University (CMU) realized this application by Manuel Blum and Luis von Ahn, etc. - CAPTCHA, commonly known as "verif...

AI Technical Summary

Problems solved by technology

[0006] The successful cracking of the above CAPTCHA shows that the current CAPTCHA still has some defects, the main performance is as follows: there is no good connection between characters and it is easy to split, such as Figure 1c

And some are too sticky to cause blurred characters, such as Figure 1b As shown, the "rn" and "m" will be misrecognized

Images