Glossary
138
Proxy Server
A proxy server resides between a Web client, such
as a web browser, and a real Web server and acts
as an intermediary between them. When some
people browse a web site, their browser is not
actually connecting to the web server. The request
from their browser goes to a proxy server, and the
proxy server makes the request to the web server.
A proxy server can improve performance for groups
of users because it caches the results of all requests
for a certain amount of time. If a user requests a
web page that it already loaded for another user, it
reloads the page instead of forwarding the request
to the Web server, which can be a time-consuming
operation.
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 traveling for example).
SDN (Service Dialing Numbers)
Telephone numbers supplied by your network
provider and giving access to special services, such
as voice mail, directory inquiries, customer support
and emergency services.
Glossary
139
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.
Soft Keys
Two keys marke
d and
on the phone, the
purpose of which:
• varies according to the function that you are
currently using
• is indicated on the bottom line of the display just
above the corresponding key.
Voice Mail
Computerized answering service that automatically
answers your calls when you are not available,
plays a greeting (optionally in your own voice) and
records a message.
