Short for completely automated public turing test to tell computers and humans apart, a technique used by a computer to tell if it is interacting with a human or another computer. Because computing is becoming pervasive, and computerized tasks and services are commonplace, the need for increased levels of security has led to the development of this way for computers to ensure that they are dealing with humans in situations where human interaction is essential to security. Activities such as online commerce transactions, search engine submissions, Web polls, Web registrations, free e-mail service registration and other automated services are subject to software programs, or bots, that mimic the behavior of humans in order to skew the results of the automated task or perform malicious activities, such as gathering e-mail addresses for spamming or ordering hundreds of tickets to a concert.
In order to validate the digital transaction, using the CAPTCHA system the user is presented with a distorted word typically placed on top of a distorted background. The user must type the word into a field in order to complete the process. Computers have a difficult time decoding the distorted words while humans can easily decipher the text. Some CAPTCHAs now use pictures instead of words where the user is presented with a series of pictures and asked what is the common element among all of the pictures. By entering that common element, the user validates the transaction and the computer knows it is dealing with a human and not a bot.
The word public in the term refers to the fact that the algorithm used is made public instead of being held secret. The idea is that breaking the scurity of a CAPTCHA depends on artifical intelligence; discovering the algorithm itself does not defeat the security measures. The term was coined by Luis von Ahn, Manuel Blum and Nicholas J. Hopper of Carnegie Mellon University, and John Langford of IBM in 2000.
Acronym for Common Address Redundancy Protocol. CARP is a free alternative to the Virtual Router Redundancy Protocol (VRRP) and the Hot Standby Router Protocol (HSRP). Its primary purpose is to allow multiple hosts on the same network segment to share an IP address. CARP works by allowing a group of hosts on the same network […]
Short for Computer Aided Software Engineering, a category of softwarethat provides a development environment for programming teams. CASE systems offer tools to automate, manage and simplify the development process. These can include tools for: Summarizing initial requirements Developing flow diagrams Scheduling development tasks Preparing documentation Controlling software versions Developing program code Various companies offer CASE […]
Short for constant angular velocity, a technique for accessing data off of rotating disks. With CAV, the disk rotates at a constant speed regardless of what area of the disk is being accessed. This differs from Constant Linear Velocity (CLV), which rotates the disk faster for inner tracks. Disk drives use CAV, whereas CD-ROMs generally […]
On eBay, eBay alternatives, and classified ad Web sites, CAYOR is an abbreviation used to mean cash at your own risk. This abbreviation is used by the seller to indicate that if the buyer chooses to pay cash for the item, and mail cash to the seller, the buyer is not responsible for missing or […]
Short for Common Biometric Exchange Formats Framework, it is a standard format for exchanging biometric data between different biometric devices and systems.