A primary advantage of
WLANs is mobility, but no industry standard currently addresses the
tracking or management of mobile devices in its Management
Information Base (MIB). This omission would prohibit users from
roaming between wireless access points that cover a common area,
such as a complete floor of a building. Individual companies such as
Cisco have addressed this issue, providing their own versions of
mobility algorithms that facilitate roaming within an IP domain
(such as a floor) with an eye toward optimizing roaming across IP
domains (such as an enterprise campus).
Management
Wireless access points share the
functions of both hubs and switches. Wireless clients associating
with access points share the wireless LAN, similar to the way a hub
functions, but the access point can additionally track movement of
clients across its domain and permit or deny specific traffic or
clients from communicating through it. For network managers to use
these services to their advantage, it is necessary to instrument the
access point like a hub and a switch.
The Cisco WLAN devices are manageable
through common Telnet or SNMP (I or II) services and a Web browser
interface to facilitate its monitoring and control. In addition to
bridge statistics and counters, the access point also offers
additional features that make it powerful and manageable, including
mapping of wireless access points and their associated clients as
well as monitoring and reporting of client statistics. Access points
can also control access and the flow of traffic through the wireless
LAN via MAC and protocol-level access lists. Configuration
parameters, as well as code images for access points, can be
centrally configured and managed to facilitate consistency of WLAN
network policy.