Short for Challenge Handshake Authentication Protocol, a type of authentication in which the authentication agent (typically a network server) sends the client program a random value that is used only once and an ID value. Both the sender and peer share a predefined secret. The peer concatenates the random value (or nonce), the ID and the secret and calculates a one-way hash using MD5. The hash value is sent to the authenticator, which in turn builds that same string on its side, calculates the MD5 sum itself and compares the result with the value received from the peer. If the values match, the peer is authenticated.
By transmitting only the hash, the secret can’t be reverse-engineered. The ID value is increased with each CHAP dialogue to protect against replay attacks.
Contrast with PAP.
Short for change mode, a UNIX command that changes the access permissions of files or directories in order to read, write or execute files.
Pronounced chirp. Short for Common Hardware Reference Platform, a specification for PowerPC -based machines that can run the Mac OS, Windows NT, or AIX. First released in 1996, CHRP was supposed to make it possible for computer vendors to build Macintosh clones as well as PowerPC-based NT computers. CHRP is also called the PowerPC Platform […]
Short for Customer Information Control System, a TP monitor from IBM that was originally developed to provide transaction processing for IBM mainframes. It controls the interaction between applications and users and lets programmers develop screen displays without detailed knowledge of the terminals being used. CICS is also available on non-mainframe platforms including the RS/6000, AS/400 […]
- CIE color model
(n.) A color model based on human perception developed by the CIE (Commission Internationale de l’Eclairage) committee. While widely regarded as the most accurate color model, CIE is unsuitable for many technologies, including color printing and color monitors. Consequently, these systems need to use other color models, such as CMYK and RGB.
- Common Internet File System (CIFS)
Short for Common Internet File System, a protocol that defines a standard for remote file access using millions of computers at a time. With CIFS, users with different platforms and computers can share files without having to install new software. CIFS runs over TCP/IP but uses the SMB (Server Message Block) protocol found in Microsoft […]