9 search results - page 2 / 2 » Density-based spam detector |
WWW
2009
ACM
14 years 6 months ago
2009
ACM
We present a new CAPTCHA which is based on identifying an image's upright orientation. This task requires analysis of the often complex contents of an image, a task which hum...
SOUPS
2006
ACM
13 years 11 months ago
2006
ACM
Unicode is becoming a dominant character representation format for information processing. This presents a very dangerous usability and security problem for many applications. The...
NDSS
2009
IEEE
14 years 22 hour ago
2009
IEEE
Several off-the-shelf products enable network operators to enforce usage restrictions by actively terminating connections when deemed undesirable. While the spectrum of their appl...
SIGOPS
2011
13 years 7 days ago
2011
Secure, fault-tolerant distributed systems are difficult to build, to validate, and to operate. Conservative design for such systems dictates that their security and fault toleran...