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Glossary
Gigaset DE410 IP PRO / en / A31008-M2219-L101-5-7619 / glossary.fm / 27.09.2012
PRO Version 3, 30.05.2012
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 con-
trol data transfer, a STUN server is also required on the Internet. STUN cannot be imple-
mented with symmetric NATs.
See also: ALG, Firewall, NAT, Outbound proxy.
Subnet
Segment of a network.
Subnet mask
IP addresses consist of a fixed line network number and a variable subscriber number. The
network 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 network number and the last part is 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.
T
TCP
Transmission Control Protocol
Transport protocol. Session-based transmission protocol: it sets up, monitors and termi-
nates a connection between sender and recipient for transporting data.
TLS
Transport Layer Security
Protocol for encrypting data transmissions on the Internet. TLS is a superordinate trans-
port protocol.
Transmission rate
Speed at which data is transmitted in the WAN or LAN. The transmission rate is measured
in data units per unit of time (Mbit/s).
Transport protocol
Controls data transport between two communication 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 estab-
lish a fixed connection. The recipient is solely responsible for making sure the data is
received. The sender is not notified about whether it is received or not.
