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CHAP Challenge Handshake Authentication Protocol. Part of the PPP protocol to ensure authentication of the connection between two devices.
Class Type of IP address. IP addresses fall into three main classes, A, B and C.
Client A user whom is making use of a particular system resource or peripheral through a workstation attached to a local or wide area network.
Client/server A user who is attached to a file server to recover and store files, but the processing of the data or use of an application is carried out on the client machine.
Coaxial cable A
CSMA/CD Carrier Sense Multiple Access with Collision Detection, the Ethernet protocol that allows each device to create and send its own data packets. CSMA/CD is used to avoid excessive collisions between packets as they are randomly transmitted. A CSMA/CD device first listens for other carriers, if it detects no other carriers, it will then allow the data packet to be transmitted. If a collision is detected, the device stops transmitting, waits a random length of time, and begins transmitting again.
D Channel A control channel carrying signalling information, running at 16 Kbps. The basic rate ISDN 2 service carries two B channels plus one control D channel. Refer to ISDN and B Channel.
Data Characters or code either entered by the user or passed between devices that are part of the computer or network.
Data communications The transfer of data via transceiver equipment by means of data transmission according to a protocol. Refer to Protocol.