Teldat elmeg IP120, User Manual

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elmeg IP120 / en / elmegIP120_v1 / glossary.fm / 01.08.2012
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Teldat Glossary
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 inter-
nal 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 transport
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 establish
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.
URI
Uniform Resource Identifier
Character sequence for identifying resources (e.g., e-mail recipient, www.teldat.com, files).
On the
Internet, URIs are used as a unique 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 sub-
scriber with VoIP equipment.
URL
Universal Resource Locator
Globally unique address of a domain on the Internet .
A URL is a subtype of the URI . URLs identify a resource by its location on the Internet . For his-
torical reasons the term is often used as a synonym for URI.