This MIB is intended to be implemented on all those
devices operating as Central Controllers (CC) that
terminate the Light Weight Access Point Protocol
(LWAPP) tunnel from Light-weight Access Points.
Link Test is performed to learn the backhaul link
quality between two mesh neighboring mesh nodes.
The arrangement of the controller
(referred to as CC in the diagram) and mesh nodes
(RAP and MAP) LWAPP APs ,client(MN) and NMS appear
as follows.
+.......+ +.......+
+ + + +
+ NMS + + NMS +
+ + + +
+.......+ +.......+
. .
. . . .
. . . .
. . . .
+......+ +......+ +......+ +......+
+ + + + + + + +
+ CC + + CC + + CC + + CC +
+ + + + + + + +
+......+ +......+ +......+ +......+
.. . . .
.. . . .
. . . . .
. . . . .
. . . . .
. . . . .
+......+ +......+ +......+ +......+ +......+
+ + + + + + + + + +
+ RAP + + RAP + + RAP + + RAP + + RAP +
+ + + + + + + + + +
+......+ +......+ +......+ +......+ +......+
. . . . .
. . . . .
. . . . .
. . . . .
. . . . .
+......+ +......+ +......+ +......+ +......+
+ + + + + + + + + +
+ MAP + + MN + + MAP + + MAP + + MAP +
+ + + + + + + + + +
+......+ +......+ +......+ +......+ +......+
. . .. .
. . . .. .
. . . .. .
. . . . .
+......+ +......+ +......+ +......+. +......+
+ + + + + + + + + +
+ MAP + + MAP + + MAP + + MAP + + 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. The
controllers and the IDS systems exchange information
through Cisco proprietary event exchange mechanisms.
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 them to the controller to which
it is logically connected.
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'.
Mobile Node ( MN )
A roaming 802.11 wireless device in a wireless
network associated with an access point. Mobile Node
and client are used interchangeably.
Network Management System ( NMS )
The station from which the administrator manages the
wired and wireless networks.
Mesh Node
A mesh node is defined as a physical or logical entity
in the mesh network participating in forming the mesh
backhaul. There are two types of mesh nodes supported
in Cisco mesh network:RAP and MAP.
Root AP (RAP)
The AP forming the bridge between a wired and a mesh
network with an Ethernet interface to the wired
network and a 802.11 radio interface to the mesh
network
Mesh AP (MAP).
The AP extending wireless coverage similar to a
repeater in a mesh network and consists of a 802.11
uplink and a 802.11 downlink. On a single-radio
backhaul, both uplink and downlink exist on the same
radio and are logical links only. On a multi-radio
backhaul, they may exist on different radios.MAP APs
associates directly with RAP APs or with another MAP
AP. Each association of AP (MAP-MAP or RAP-MAP) with
another AP forms parent-child relationship.
Mesh Network
Network starting with the wireless backhaul downlink
of the RAP and all the entities below except any
attached network to the Ethernet link of MAPs. A mesh
network below a single RAP is also referred to as a
'Mesh Sector'.A mesh network consists of mesh nodes.
A single mesh network is always augmented to a single
wired network.
Mesh Link
A logical 802.11 link between two mesh nodes. A single
link is point-to-point. All point-to-multipoint links
are considered as multiple mesh links. Often referred
to as mesh backhaul link.
Mesh Backhaul
A Mesh backhaul consists of mesh nodes and mesh links
terminating at a RAP. This necessarily creates a one-
to-one relationship between a 'mesh network', 'mesh
sector' and a 'mesh backhaul' where these terms can be
used interchangeably.
SNR
Signal to Noise ratio on the 802.11 radio.
Bridged network
The bridged network is defined as the network(s)
attached to the Ethernet port of any MAP. There can be
multiple such networks attached to a single mesh
network.
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