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Glossary
Gigaset DE900 IP PRO / en / A31008-M2210-R101-3x-7619 / glossary.fm / 22.03.2011
Version 2, 27.05.2010
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 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 ter-
minates 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
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 communication partners (applications).
See also: UDP, TCP, TLS.
