Glossary
Rev 3.5 Feb.05 61
roaming A cellular subscriber is in an area where service is obtained
from a cellular service provider that is not the subscriber’s
provider.
SMS Short message services—A feature that allows users of a
wireless device on a wireless network to receive or transmit
short electronic alphanumeric messages (up to 160 characters,
depending on the service provider).
system tray Usually located in the lower right corner of your screen, or the
Today screen of PocketPCs. Also known as the (Windows)
status area.
TCP Transmission Control Protocol—The common underlying
communication protocol used on the Internet. A connection
handshake establishes a point to point logical connection. In
contrast to UDP, TCP ensures both ends of the connection are
present and active on the network. TCP ensures delivery of
datagrams.
TDD Telecommunications Device for the Deaf. See TTY
TIA Telecommunications Industry Association—A standards
setting trade organization, whose members provide communi-
cations and information technology products, systems, distri-
bution services and professional services in the United States
and around the world. Consult www.tiaonline.org.
TTY Tele TYpe—Refering to early wireline data terminals, it now
applies to devices used to aid hearing and speech impaired
people to use the telephone system.
UDP User Datagram Protocol—A low overhead, connectionless,
packet delivery IP protocol. Unlike TCP, UDP does not
guarantee delivery of datagrams.
VPN Virtual Private Network
WiFi Wireless Fidelity—a high-frequency wireless local area
network (WLAN), known as 802.11.