Appendix
34
Router
A data transfer device that checks the target address for a message and
selects the best route. A router receives data packages from a network,
processes data connections and network layer protocols, and then sends
the data packages via appropriate data connections and network layer
protocols to another network.
Sub-network mask
A sub-network mask or network mask is comprised of four figures and is
structured like an IP address. It may be provided by the ISP as part of the
TCP/IP statements. It enables the IP addresses that are restricted to a
particular network to be defined (in contrast to valid IP addresses that are
recognized throughout the Internet).
Switch
Option for connecting several computers to a network. Hubs used to be
used as well.
TCP/IP
Transmission Control Protocol / Internet Protocol. Standard protocol for
transmitting data in the Internet Standard protocol for transmitting data in
the Internet
UDP
One of the protocols on which the Internet is based. In contrast to TCP,
which controls whether the packages arrive at a particular target computer
and are correctly sorted during data transmission, UDP provides no error
correction.
Upstream
Data flow towards the Internet.
Virtual server/port forwarding
Option for using server applications behind a firewall through targeted
forwarding of the ports used to a firmly, defined IP address.
