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Glossary
S
Server
Provides a service to other
(
). The term
can indicate a computer/PC or an application. A server is addressed via
SIP (Session Initiation Protocol)
Signaling protocol independent of voice communication. Used for establish-
ing and ending a call. It is also possible to define parameters for voice trans-
mission.
SIP address
See
.
SIP port/Local SIP port
that is used to send and receive SIP signaling data for VoIP.
SIP provider
See
SIP proxy server
IP address of your VoIP provider's gateway server.
Static IP address
A static IP address is assigned to a network component manually during net-
work configuration. Unlike a
a static IP address never
changes.
STUN
Simple Transversal of UDP over NAT
NAT control mechanism.
STUN is a data protocol for VoIP telephones. STUN replaces the private
IP address in the data packets of the VoIP telephone with the public address
of the secure private network. To control data transfer, a STUN server is also
required on the Internet. STUN cannot be implemented with symmetric
.
Subnet
Segment of a
.
Subnet mask
consist of a fixed network number and a variable subscriber
number. The network number is identical for all
.
The size of the network number part is determined in the subnet mask.
In the subnet mask 255.255.255.0, for example, the first three parts of the
IP address are the network number and the last part the subscriber number.
Symmetric NAT
A symmetric NAT assigns different external IP addresses and port numbers
to the same internal IP addresses and port numbers – depending on the
external target address.