| This MIB module defines objects that describes the
configuration and status of the spectrum intelligence
capabilities of the 802.11 Access points.
This MIB is intended to be implemented on all those
devices operating as Central Controllers (CC) that
terminate the Light Weight Access Point Protocol
tunnel from Light-weight LWAPP Access Points.
The relationship between CC and the LWAPP APs
can be depicted as follows:
+......+ +......+ +......+ +......+
+ + + + + + + +
+ CC + + CC + + CC + + CC +
+ + + + + + + +
+......+ +......+ +......+ +......+
.. . . .
.. . . .
. . . . .
. . . . .
. . . . .
. . . . .
+......+ +......+ +......+ +......+ +......+
+ + + + + + + + + +
+ AP + + AP + + AP + + AP + + AP +
+ + + + + + + + + +
+......+ +......+ +......+ +......+ +......+
. . . .
. . . . .
. . . . .
. . . . .
. . . . .
+......+ +......+ +......+ +......+ +......+
+ + + + + + + + + +
+ MN + + MN + + MN + + MN + + MN +
+ + + + + + + + + +
+......+ +......+ +......+ +......+ +......+
The LWAPP tunnel exists between the controller and
the APs. The MNs communicate with the APs through
the protocol defined by the 802.11 standard.
LWAPP APs, upon bootup, discover and join one of the
controllers and the controller pushes the configuration,
that includes the WLAN parameters, to the LWAPP APs.
The APs then encapsulate all the 802.11 frames from
wireless clients inside LWAPP frames and forward
the LWAPP frames to the controller.
GLOSSARY
Access Point ( AP )
An entity that contains an 802.11 medium access
control ( MAC ) and physical layer ( PHY ) interface
and provides access to the distribution services via
the wireless medium for associated clients.
LWAPP APs encapsulate all the 802.11 frames in
LWAPP frames and sends it to the controller to which
it is logically connected.
Basic Service Set Identifier (BSSID)
The identifier for the service set comprising of
all the 802.11 stations under the control of
one coordinating Access Point. This identifier
happens to be the MAC address of the dot11 radio
interface of the Access Point. The wireless
clients that associate with the Access Point
get the wired uplink through this particular
dot11 interface.
Central Controller ( CC )
The central entity that terminates the LWAPP protocol
tunnel from the LWAPP APs. Throughout this MIB,
this entity also referred to as 'controller'.
Light Weight Access Point Protocol ( LWAPP )
This is a generic protocol that defines the
communication between the Access Points and the
Central Controller.
Mobile Node ( MN )
A roaming 802.11 wireless device in a wireless
network associated with an access point.
Station Management (SMT)
This term refers to the internal management of the
802.11 protocol operations by the AP to work
cooperatively with the other APs and 802.11
devices in the network.
Spectrum Intelligence (SI)
Radio frequency (RF) interference from devices
operating in the unlicensed 2.4-GHz and 5-GHz
bands used by wireless LANs (WLANs) is a growing
concern for organizations deploying indoor and outdoor
wireless networks. A variety of RF devices are now
available that can cause interference, including
cordless phones, Bluetooth devices, cameras, paging systems,
unauthorized access points, and clients in ad-hoc mode.
Left unaddressed, RF interference can result in low data
rates and throughput, lack of sufficient WLAN coverage,
WLAN performance degradation, poor voice quality, and low
end-user satisfaction. This, in turn, can lead to decreased
network capacity, an increase in support calls,
network downtime, rising operational costs, and potential
security vulnerabilities from malicious interference.
Spectrum Intelligence, industry-leading solution from Cisco
detects, classifies, and locates devices causing RF
interference in the unlicensed 2.4-GHz and 5-GHz bands.
When the source of the interference is determined,
customers can remove, move, shield, adjust, or replace the
interference source. This helps organizations troubleshoot
the wireless network to determine the root causes of
interference problems and optimize network performance.
Sensord
The Sensord software looks at the timing and frequency of
interference bursts, and the discovered attributes of the
bursts such as the modulation type and identified sync words.
This high-level information is then used to perform the final
identification and separation of one device from another.
This final classification step provides the powerful features
of SI: Identifying the specific source of the interference,
where it is located, and how it can be mitigated.
Persistent Device Propagation
Interference devices usually affect multiple wireless
access points. Using persistent device propagation information
regarding persistent interference devices can be passed from one
access point to another access point effectively improving
radio resource management.
Radio Resource Management ( RRM )
RRM is the system level control of co-channel
interference and other radio transmission
characteristics in wireless communication systems.
REFERENCE
[1] Part 11 Wireless LAN Medium Access Control ( MAC )
and Physical Layer ( PHY ) Specifications.
[2] Draft-obara-capwap-lwapp-00.txt, IETF Light
Weight Access Point Protocol. |
