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Comparative Study of Algorithms used in CAPTCHA’s and New Finding Set as LCG Algorithm


  • Vels University, Chennai – 600117, Tamil Nadu, India
  • School of computing sciences, Vels University, Chennai – 600117, Tamil Nadu, India


Objectives: The completely automated public Turing tests are used generally to find the difference between the users whether he/she is a human or a bot. Methods: Once the randomly generated characters are held then it is converted into ASCII characters and this method will generate symbols, numbers and alphabets. As this very tedious one which is very difficult to be understood by bots so this method is very effective and robust. Findings: Number of authentication purpose is found out by misplacing the word’s style and fonts. Very simple issues can be solved by this captcha’s approach. The methods are very complicated for humans to understand but on the same side, it is easy for robots to keenly understand. So a new algorithm is used to find understandable captcha’s into tougher one. Also, the LCG algorithm providesonly the designing principles to be followed in it by giving random function use. Application/Improvements: The main improvisation done here is that the application is built with more secure line and its usability is too high



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