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 Cisco Light-weight LWAPP Access Points.

This MIB helps to manage the Radio Frequency (RF) 
parameters on the controller.

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 to.

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
controllers.

Mobile Node ( MN )

A roaming 802.11 wireless device in a wireless
network associated with an access point. 

802.1x

The IEEE ratified standard for enforcing port based
access control.  This was originally intended for
use on wired LANs and later extended for use in
802.11 WLAN environments.  This defines an
architecture with three main parts - a supplicant
(Ex. an 802.11 wireless client), an authenticator
(the AP) and an authentication server(a Radius
server).  The authenticator passes messages back
and forth between the supplicant and the
authentication server to enable the supplicant
get authenticated to the network.

Radio Frequency ( RF )
       
Radio frequency (RF) is a rate of oscillation in the 
range of about 3 kHz to 300 GHz, which corresponds to 
the frequency of radio waves, and the 
alternating currents which carry radio signals.

Received Signal Strength Indicator ( RSSI )

A measure of the strength of the signal as
observed by the entity that received it,
expressed in 'dbm'.

Coverage Hole Detection ( CHD )

If clients on an Access Point are detected at low 
RSSI levels, it is considered a coverage hole  
by the Access Points. This indicates the existence 
of an area where clients are continually getting poor 
signal coverage, without having a viable location to 
roam to.


REFERENCE

[1] Wireless LAN Medium Access Control ( MAC ) and
Physical Layer ( PHY ) Specifications.

[2] Draft-obara-capwap-lwapp-00.txt, IETF Light 
Weight Access Point Protocol 

[3] IEEE 802.11 - The original 1 Mbit/s and 2 Mbit/s, 
2.4 GHz RF and IR standard.