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Glossary
port what is known as the SIP standard. SIP is the current
standard defined for VoIP by the IETF (Internet Engineering
Task Force).
WLAN
abbreviation for Wireless Local Area Network
The term WLAN designates the industry standard for wireless
local networks passed by the Institute of Electrical and Elec-
tronics Engineers (IEEE) in 1997 under the title IEEE 802.11.
By means of WLAN technology, individual PCs or network de-
vices like printers or DSL access points can be linked wireles-
sly to an existing cable-connected local network (LAN), or
LANs can be converted completely to a wireless structure. A
further useful purpose for WLAN technology is to link seg-
ments of existing cable-connected networks.
Although WLAN was actually developed only for short-range
connections, by cascading WLAN access points or implement-
ing transmission networks with high-power point-to-point ra-
dio transmission, even network segments located further
from each other can be linked or network participants in rela-
tively remote locations can be economically and easily inte-
grated into an existing network.
WLAN access points often also serve as access points to the
Internet in private or public institutions. Many airports, hotels
and cafes, for instance, make WLAN hotspots available to
their customers, either free or subject to a charge. Ultimately
this has maneuvered WLAN into serious competition with mo-
bile UMTS technology.
The application possibilities for wireless network communi-
cation also overlap with Bluetooth technology. For mobile de-
vices with limited energy capacity Bluetooth is the more use-
ful solution, however, as Bluetooth uses considerably less
power than wireless LAN. What is more, Bluetooth technology
is more flexible and thus can offer a greater bandwidth of po-
tential applications.
