Glossary
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Protocol
A set of rules governing the transmission of
data. In order for a data transmission to work,
both ends of the connection have to follow the
rules of the protocol.
Public IP Address
A public IP address is a globally unique
number that identifies a device on the
Internet. Anyone on the Internet can connect
to the device using the public address.
PUK
Personal Unblocking Key.
A secret code made up of 8 to 10 digits. The
PUK is used to reactivate a SIM card that has
been blocked.
Roaming
The movement between microcells in a radio
network. Roaming service is used to provide
network access independent of where the
user resides and what service provider that is
running the network.
Routing
The forwarding of data between a local
network and the Internet on the most efficient
route, based on the data’s destination IP
address and current network conditions. A
device that performs routing is called a router.
RSSI
Received Signal Strength Indicator.
The RSSI is an indicator of the strength of the
received radio signal.
SIM
Subscriber Identity Module.
The “smart card” required by all mobile
customers to operate their phones. Carries
authentication, billing and information about
the individual subscriber, as well as address
book and other personalized information.
SSID
Service Set Identifier.
A unique network name that differentiates
one wireless device from another. Wireless
PCs configured with the same SSID can
access the same network.
Subnet
A portion of a network. The subnet is
distinguished from the larger network by a
subnet mask that selects some of the
computers of the network and excludes all
others. The subnet’s devices remain
physically connected to the rest of the
network, but they are treated as though they
were on a separate network.
Subnet mask
A mask that defines a subnet. See also
Network mask.
Switching
Routing data traffic by setting up temporary
connections between two or more network
points. This will take the data toward its
intended destination.
TCP
Transmission Control Protocol.
See TCP/IP.
TCP/IP
Transmission Control Protocol / Internet
Protocol.
The basic protocols used on the Internet.
TCP is responsible for dividing data up into
packets for delivery and reassembling them
at the destination. IP is responsible for
delivering the packets from source to
destination. When TCP and IP are bundled
with higher-level applications such as HTTP,
FTP, Telnet, and so on, TCP/IP refers to this
whole suite of protocols.
TFTP
Trivial File Transfer Protocol.
A TCP/IP protocol commonly used for
software downloads.
