This MIB is intended to be implemented on those Network
Management applications that manage a network of wireless
devices through the Controller and send relevant management
information to Northbound Operation Support Systems. The
Northbound OSS, with the information received shall present a
consolidated view of the whole network of wireless devices. 

The NM learns the status of the managed devices from the
Controller through interfaces like the SNMP, and raises
events. Depending upon the event severity, alerts are raised
for the events. The alert/event information is sent to the
Northbound OSS in the form of SNMP Notifications. This MIB
defines these Notifications.

The MIB objects cWNotificationDescription,
cWNotificationSpecialAttributes and cWNotificationVirtualDomains
have been defined to have a maximum size of 1024.   The bigger
size is required for the following reasons.

1. If the size is reduced, the information intended to be 
sent to the Northbound applications will be truncated / lost. 

2. Networks using UDP are better in handling fragmentation than
before. 

3. In case if the implementation is used in those networks that
can't handle Notifications of a larger size,  the intent is to
suggest the use of the TCP as the transport protocol for SNMP as
against the UDP. 

4. The respective objects may not have the maximum defined range
at all the times.  The higher range is just to accommodate those
cases where the size can hit the maximum value. 

The relationships between NCS, CC, AP, MN and
Mgmt-Appl can be depicted as follows :                

   +................+     +................+
   +                +     +                +
   +  NB OSS 1      + ..  +  NB OSS n      +
   +                +     +                +
   +................+     +................+
                ^               ^
                  .           . 
                    .       .    Notifications
                      .   .
                        .
                 +..........+
                 +          +
                 +    NCS   +
                 +          + 
                 +..........+
                  ^    ^   ^
                .      .     .   SNMP
              .        .       .
            .          .         .
          .            .           .
      +......+     +......+     +......+
      +      +     +      +     +      +
      +  CC  +     +  CC  +     +  CC  +
      +      +     +      +     +      +
      +......+     +......+     +......+
        ..            .             .
       .  .            .             .
      .    .            .             .
     .      .            .             .
    .        .           .             .
+......+ +......+     +......+      +......+
+      + +      +     +      +      +      +
+  AP  + +  AP  +     +  AP  +      +  AP  +
+      + +      +     +      +      +      +
+......+ +......+     +......+      +......+
           .              .             .
         .  .              .             .
        .    .              .             .
       .      .              .             .
      .        .              .             .
   +......+ +......+     +......+      +......+
   +      + +      +     +      +      +      +
   +  MN  + +  MN  +     +  MN  +      +  MN  +
   +      + +      +     +      +      +      +
   +......+ +......+     +......+      +......+  


                   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.

Alert

An alert is an NM response to one or more related Events from
Managed Object. If the Event learnt is severe enough to let the
user know about, the NM raises an alert i.e if event has one of
the following severity critical, major, minor or warning. One
or more Events can result in a single alert being raised.

Central Controller ( CC )

The central entity that terminates the LWAPP protocol
tunnel from the LWAPP APs.  Throughout this MIB,
this entity is also referred to as 'Controller'.

Event

An Event is an occurrence or detection of some condition in and
around the network. Event can be generated by the NM
corresponding to traps received or through polling the managed
object.

Light Weight Access Point Protocol ( LWAPP )

This is a generic protocol that defines the
communication between the Access Points and the
Controllers.

Managed Object

Managed Objects are used to represent those entities being 
managed by the NM.  It could be an AP, WLAN, Controller or 
an MN.

Mobile Node ( MN )

Mobile Nodes are roaming 802.11 wireless devices that would 
associate to an AP to get their uplink to the wired network. 
Mobile Nodes are also known as clients.

Network Management Application ( NM )

Application which manages network of managed objects using
SNMP. It provides network management functions of FCAPS -
Fault, Configuration, Accounting, Performance and Security to
manage the network.

Notification

NM application like NCS sends Notifications defined through
this MIB, corresponding to their Alerts and Events to a 
Northbound OSS to provide a consolidated view.

Operations Support Systems ( OSS )

Management applications in the network that receive
Notifications from NM (like NCS) and provide consolidated view 
of the whole network of wireless devices.

Received Signal Strength Indicator ( RSSI )

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

Signal-Noise Ratio ( SNR )

A measure of the quality of the signal relative to the strength
of noise expressed in 'dB'.

Virtual Domain

A NM's Virtual Domain is a logical grouping that consists of a
set of managed objects like Controllers, APs, WLANs, maps etc.
It restricts a user's view to information relevant to these
managed objects. Through a virtual domain, an administrator can
ensure that users are only able to view the managed objects and
maps for which they are responsible. A managed object can belong
to more than one virtual domain.

Network Control System ( NCS )

Network Control System (NCS) is a converged platform for 
wired, wireless, and security policy management in a single 
solution for faster troubleshooting and more efficient network 
operations. 


Wireless LAN ( WLAN ) 

A WLAN refers to the network of IEEE 802.11 complaint wireless 
devices within mutual communication range of each other via 
the wireless medium.

REFERENCE

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

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