Samsung SGH-Z107 User Manual page 130

Packet-Switched
A type of network in which relatively small units
of data called packets are routed through a
network based on the destination address
contained within each packet. Today's Internet is
fundamentally a quintessential packet-switched
network. Whereas voice requires a smooth flow
of traffic to avoid echo and breakup, data can be
cut into small packets with each being sent
across the network and reassembled at the final
destination. Packet inevitably allows a greater
amount of users because it does not require a
dedicated open circuit. PDC-P in Japan, GPRS in
Europe and all the future 3G networks will be
packet-switch.
PIN (Personal Identification Number)
Security code that protects the phone/SIM
against unauthorised use. The PIN is supplied by
the service provider with the SIM card. It may be
a four to eight-digit number and can be changed,
as required.
PUK (PIN Unblocking Key)
Security code used to unlock the phone when an
incorrect PIN has been entered three times in
succession. The eight-digit number is supplied by
the service provider with the SIM card.
Roaming
Use of your phone when you are outside your
home area, when travelling for example.
SIM (Subscriber Identification Module)
Card containing a chip with all the information
required to operate the phone (network and
memory information, as well as the subscriber's
personal data). The SIM card fits into a small slot
on the back of the phone and is protected by the
battery.
SMS (Short Message Service)
Network service sending and receiving messages
to and from another subscriber without having to
speak to the correspondent. The message
created or received can be displayed, received,
edited or sent.
UMTS (Universal Mobile
Telecommunications System)
A 3rd generation (3G) mobile communications
technology that promises data transmission
speeds of up to 2 megabits per second (Mbps).
Glossary
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