Telling humans and computers apart automatically
read more
Citations
CAPTCHA: using hard AI problems for security
reCAPTCHA: Human-Based Character Recognition via Web Security Measures
Recognizing objects in adversarial clutter: breaking a visual CAPTCHA
SybilLimit: A Near-Optimal Social Network Defense against Sybil Attacks
Efficient shape matching using shape contexts
References
Computing Machinery and Intelligence
Recognizing objects in adversarial clutter: breaking a visual CAPTCHA
Securing passwords against dictionary attacks
Method for selectively restricting access to computer systems
Pessimal print: a reverse Turing test
Related Papers (5)
Frequently Asked Questions (6)
Q2. Why do some companies maintain their prices?
Part ofthe reason these companies can maintain their prices is because of advertisements: users see various products or brands being advertised while they shop.
Q3. What is the reason for making a captcha public?
If a captcha requires private data in order to be secure, then this captcha isvulnerable to hacker attacks: once a hacker breaks into the system and finds this secret data, the captcha ceases to be secure forever.
Q4. What is the way to steal cycles from intelligent people?
Notice that captchas are the ultimate tool for stealing cycles from intelligent people: malicious, intelligent programmers (writing programs that get thousands of free email accounts, etc.) can be put to work on hard unsolved AI problems.
Q5. What is the way to solve the captcha problem?
The porn companies can have bots that try to get free email accounts, and as soon as the bots encounter a captcha test, they simply send the test to the porn site.
Q6. What is the way to make a captcha?
One way for pix to become a captcha is to randomly distort the images before presenting them to the user, in such a way that searching the database for the images is hard for current computer programs.•