Network Card User Manual

WLAN-IEEE802.11 Tutorial (Maximilian Riegel), 021018-wlan-tutorial.ppt Page 11 © Siemens, 2002
What is unique about wireless?
n Difficult media
– interference and noise
– quality varies over space and time
– shared with “unwanted” 802.11 devices
– shared with non-802 devices (unlicensed spectrum, microwave ovens)
n Full connectivity cannot be assumed
– “hidden node” problem
n Mobility
– variation in link reliability
– battery usage: requires power management
– want “seamless” connections
n Security
– no physical boundaries
– overlapping LANs
n Multiple international regulatory requirements