3Com CommWorks 5210 - Manual (Page 131)

Appendix : Glossary 131
CSMA Carrier Sense Multiple Access—Media-access mechanism wherein devices ready to
transmit data first check the channel for a carrier. If no carrier is sensed for a
specific period of time, a device can transmit. If two devices transmit at once, a
collision occurs and is detected by all colliding devices. This collision subsequently
delays retransmissions from those devices for some random length of time.
CTS Clear to Send—Hardware signal defined by the RS-232 specification that indicates
that a transmission can proceed.
CLASS Custom Local Area Signaling Services—CLASS is a service mark of Bellcore. It is the
signaling service available such as caller-id, call waiting, and auto-redial.
DCD Data Carrier Detected—Hardware signal defined by the RS-232-C specification
that indicates that a device such as a modem is online and ready for transmission.
DCE Data Communication Equipment—A communications device that can establish,
maintain, and terminate a connection (for example, a modem). A DCE may also
provide signal conversion between the data terminal equipment (DTE) and the
common carrier's channel.
DCF Disengage Confirm—This is a call flow message.
DHCP Dynamic Host Configuration Protocol—A protocol that allows network
administrators to centrally manage and automate the assignment of Internet
Protocol (IP) addresses in their organization's network.
DHTML Dynamic Hypertext Markup Languages—A name for a set of programs that
developers can use to create Web pages that update themselves on the fly.
Dynamic HTML makes your Web documents more interactive than HTML.
DIMM Dual Inline Memory Module—Has a 10% higher capacity bandwidth than Single
In-line memory module (SIMM). The DIMM’s data path is 128 bits wide.
DIN Deutsche Institute fur Normung (German Institute for Standardization)—DIN
specifications are issued under the control of the German government. The most
common specification is the dimensions of cable connectors referred to as DIN
connectors.
DINS Dialed Number Identification Service
DIP Dual Inline Package—These are small on and off switches on the circuit board
used to configure the board in a semipermanent way. The DIP switches are the
first thing to look at when a configuration isn’t what you intended after an
installation.
DMS Digital Multiplex System— A digital switch that is used in a central office . It contains
multiple devices to handle the many needs of the system. Such as, local/toll
exchange, long distance switch, international gateway, local and long distance
switch, wireless, and advanced signaling solutions.
DNS Domain Name Server—System used in the internet for translating names of
network nodes into addresses.