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Glossary
Gigaset N720 DECT IP Multicell System / engbt / A31008-M2314-L101-6-7619 / Glossary.fm / 29.08.2016
Version 2, 06.08.2010
Port
Data is exchanged between two applications in a Network via a port.
Port forwarding
The Internet gateway (e.g., your router) forwards data packets from the Internet 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 a Network subscriber. Depending on the setting in
the LAN, the port number is permanently assigned or it is assigned with each access.
The combination of IP address/Port number uniquely identifies the recipient or
sender of a data packet within a network.
Prepare dialling
See Block dialling.
Private IP address
See Local IP address.
Protocol
Describes the agreements for communicating within a Network. It contains rules for
opening, administering and closing a connection, about data formats, time frames
and possible error handling.
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 name 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 (gateway, 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 communication 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 optimising data packets.
In VoIP networks, QoS influences the voice quality. If the whole infrastructure (router,
network server etc.) has QoS, the voice quality is better, i.e., fewer delays, less echoing,
less crackling.
R
Registrar
The registrar manages the current IP addresses of the Network subscriber. When you
register with your VoIP provider, your current IP address is saved on the registrar. This
means you can also be reached when on the move.
