CAPTCHA: using hard AI problems for security
Luis von Ahn,Manuel Blum,Nicholas Hopper,John Langford +3 more
- pp 294-311
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TLDR
This work introduces captcha, an automated test that humans can pass, but current computer programs can't pass; any program that has high success over a captcha can be used to solve an unsolved Artificial Intelligence (AI) problem; and provides several novel constructions of captchas, which imply a win-win situation.Abstract:
We introduce captcha, an automated test that humans can pass, but current computer programs can't pass: any program that has high success over a captcha can be used to solve an unsolved Artificial Intelligence (AI) problem. We provide several novel constructions of captchas. Since captchas have many applications in practical security, our approach introduces a new class of hard problems that can be exploited for security purposes. Much like research in cryptography has had a positive impact on algorithms for factoring and discrete log, we hope that the use of hard AI problems for security purposes allows us to advance the field of Artificial Intelligence. We introduce two families of AI problems that can be used to construct captchas and we show that solutions to such problems can be used for steganographic communication. captchas based on these AI problem families, then, imply a win-win situation: either the problems remain unsolved and there is a way to differentiate humans from computers, or the problems are solved and there is a way to communicate covertly on some channels.read more
Citations
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Book ChapterDOI
Combating spam and denial-of-service attacks with trusted puzzle solvers
Patrick P. Tsang,Sean W. Smith +1 more
TL;DR: This work proposes the use of Trusted Computing in constructing crypto puzzles that only require each client machine to be equipped with a small tamper-resistant Trusted Puzzle Solver (TPS), which may be realized using the prevalent Trusted Platform Module (TPM) with minimal modifications.
Journal ArticleDOI
An investigation of the usability of image-based CAPTCHAs using PROMETHEE-GAIA method
TL;DR: A comparative analysis of seven image-based CAPTCHAs based on three different criteria: time to find a solution, a number of attempts, and task difficulty suggested which CAPTCHA offered better human accuracy and lower machine attack rates compared to the existing approaches.
Journal ArticleDOI
Cylindrical Coordinates Security Visualization for multiple domain command and control botnet detection
TL;DR: An in-depth investigation on the issue of botnet detection and a new security visualization tool for visualizing botnet behaviors on DNS traffic is presented, developed with the objective of enabling users to recognize security threats promptly and mitigate the damages by only visualizing DNS traffic in cylindrical coordinates.
Proceedings Article
Captchas With a Purpose.
TL;DR: This paper develops some new Captchas belonging to genre — “CAPTCHAs with a purpose” which have range of other useful purpose such as measuring reaction time of people, promoting news, general knowledge facts, jokes among people while engaging in routine activities such as checking email.
References
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