Modem Modulator De-modulator: a device used to transmit computer data over a regular telephone line
NCA National Crime Authority
Netlink A Primos/Dialcom command used to initiate a connection over an
X.25 network
NIST National Institute of Standards (US)
NIC Network Information Center (US), run by DOD: a computer which assigned domain names for the Internet.
NRL Naval Research Laboratory (US)
NSA National Security Agency (US)
NUA Network User Address: the `telephone' number of a computer on an
X.25 network
NUI Network User Identifier (or Identification): combined username/password used on X.25 networks for billing purposes
NorTel Northern Telecom, Canadian manufacturer of telecommunications equipment