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Glossary
Gigaset DX800A all in one / GBR / A31008-N3100-L101-2-7619 / Glossary.fm / 07.04.11
Version 4, 16.09.2005
SIP proxy server
IP address of your VoIP provider's gateway
server.
Static IP address
See Fixed IP address.
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
VoIP telephone data packets 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 NATs.
See also: ALG, Firewall, NAT, Outbound
proxy.
Subnet
Segment of a Network.
Subnet mask
IP addresses consist of a fixed line number
and a variable subscriber number. The net-
work number is identical for all Network
subscribers. 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 net-
work number and the last part is the sub-
scriber 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.
T
TCP
Transmission Control Protocol
Transport protocol. Session-based trans-
mission protocol: it sets up, monitors and
terminates a connection between sender
and recipient for transporting data.
TLS
Transport Layer Security
Protocol for encrypting data transmissions
on the Internet. TLS is a superordinated
Transport protocol.
Transmission rate
Speed at which data is transmitted in the
WAN or LAN. The transmission rate is meas-
ured in data units per unit of time (Mbit/s).
Transport protocol
Controls data transport between two com-
munication partners (applications).
See also: UDP, TCP, TLS.
U
UDP
User Datagram Protocol
Transport protocol. Unlike TCP, UDP is a
non session-based protocol. UDP does not
establish a fixed connection. The data pack-
ets ("datagrams") are sent as a broadcast.
The recipient is solely responsible for mak-
ing sure the data is received. The sender is
not notified about whether it is received or
not.
URI
Uniform Resource Identifier
Character string for identifying resources
(e.g., e-mail recipient, http://gigaset.com,
files).
On the Internet, URIs are used as a uniform
identification for resources. URIs are also
described as SIP addresses.
URIs can be entered in the phone as a
number. By dialling a URI, you can call an
Internet subscriber with VoIP equipment.
