ADTRAN 1203153L2, User Manual, Page: 136 / 146

Appendix F. Glossary
F-2 Express 3000 User Manual 61203153L2-20
carrier detect (CD)
A signal generated by a modem which operates over phone lines
to indicate whether the phone carrier is present and the line can be
dialed.
Customer Premises Equipment (CPE)
Communication equipment residing on the end-user's side of the
network interface boundary. In the U.S., end-user equipment that
may not be owned by the local exchange. Examples include tele-
phones and modems.
data communications equipment (DCE)
A category of devices which typically includes modems and print-
ers. DCEs interface with DTEs.
datagram
A Layer 3 data construct in which the datagram header contains
source destination addresses for routing purposes.
data terminal equipment (DTE)
User terminal equipment which creates information for transmis-
sion, for example, a user's PC.
data-circuit terminating equipment (DCE)
Carrier's equipment that is the DTE's interface to the network.
DIP switch
A very small toggle switch. The Express 3000 contains two DIP
switches: one for changing data rates and one for resetting default
parameters.
directory number
In the North American Numbering Plan, the last seven digits of a
telephone number.
Federal Communications Commission
The U.S. federal regulatory agency responsible for the regulation
of interstate and international communications by radio, televi-
sion, wire, satellite, and cable.