E quality of service (qos) – Siemens Gigaset DE380 IP R User Manual
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Glossary
Port number
Indicates a specific application of Network 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-dialing
Private IP address
Protocol
Describes the agreements for communicating within a Network. It contains
rules for opening, administering, and closing a connection, about data for-
mats, 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 Inter-
net. 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 communications networks. Differentia-
tions are made between various Quality of Service classes.
QoS influences the flow of data packets on the Internet, e.g., by prioritizing
data packets, reserving bandwidth and data packet optimization.
In VoIP networks, QoS influences 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.