Siemens Gigaset S675IP User Manual page 147

Glossary
PIN
Personal Identification Number
Protects against unauthorised use.
When the PIN is activated a number
combination has to be entered in order
to access a protected area.
You can protect your base station con-
figuration data with a system PIN (4-
digit number combination).
Port
Data is exchanged between two appli-
cations in a Network via a port.
Port forwarding
The Internet gateway (e.g. your router)
forwards data packets from the Inter-
net that are directed to a certain Port to
the port concerned. This allows servers
in the LAN to offer services on the
Internet without you needing a public
IP address.
Port number
Indicates a specific application of Net-
work subscribers. Depending on the
setting in the LAN, the port number is
permanently assigned or else it is
newly assigned with each access.
The combination of IP address/Port
number uniquely identifies the recipi-
ent or sender of a data packet within a
network.
Pre-dialling
See Block dialling.
Private IP address
See Public IP address.
Protocol
Describes the agreements for commu-
nicating within a Network. It contains
rules for opening, administering and
closing a connection, about data for-
mats, time frames and possible error
handling.
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Proxy/Proxy server
Computer program that controls the
exchange of data between Client and
Server in computer networks. If the
phone sends a query to the VoIP server,
the proxy acts as a server towards the
phone and as a client towards the
server. A proxy is addressed via IP
address/Domain names and Port.
Public IP address
The public IP address is the address for
a network component on the Internet.
It is assigned by the Internet Service
Provider. Devices that act as a link from
a local network to the Internet (gate-
way, router) have a public and a local IP
address.
See also: IP address, NAT
Q
Quality of Service (QoS)
Describes the Quality of Service in com-
munication networks. Differentiations
are made between various Quality of
Service classes.
QoS influences the flow of data packets
on the Internet, e.g. by prioritising data
packets, reserving bandwidth and data
packet optimisation.
In VoIP networks, QoS influences the
voice quality. If the whole infrastruc-
ture (router, network server etc.) has
QoS, the voice quality is better, i.e.
fewer delays, less echoing, less crack-
ling.