Glossary
GL-2
Cisco uBR7225VXR Universal Broadband Router Hardware Installation Guide
OL-17309-02
B
BER Bit error rate.
C
CATV Cable television. References to headend or distribution hub.
CCS Common channel signaling.
CES Circuit emulation service.
Chrominance The color portion of a video signal.
CMTS Cable modem termination system, such as the Cisco uBR7225VXR router.
C/N ratio Carrier-to-noise ratio.
CNR Cisco Network Registrar.
CPE Customer premises equipment.
Critical alarm An alarm condition that might affect most or all subscribers that connect to the reporting node. To
obtain more information about a problem, use the show facility-alarm status command.
See also Major alarm and Minor alarm.
CSRC Cisco Subscriber Registration Center.
CSU/DSU Channel service unit/data service unit.
CTS Clear To Send.
D
DCD Data carrier detect.
DCE Data circuit-terminating equipment (ITU-T expansion). Devices and connections of a
communications network that comprise the network end of the user-to-network interface. The DCE
provides a physical connection to the network, forwards traffic, and provides a clocking signal used
to synchronize data transmission between DCE and DTE devices. Modems and interface cards are
examples of DCE. Compare with DTE.
DHCP Dynamic Host Configuration Protocol.
DNS Domain Name System.
DOCSIS Data-over-Cable Service Interface Specification.
DSR Data set ready.