= Definizioni =
[[PageOutline(3,Indice)]]
=== Access control ===
The prevention of unauthorized usage of resources.

=== Access point (AP) ===
Any entity that has station functionality and provides access to the
distribution services, via the wireless medium (WM) for associated stations.

=== Ad hoc network ===
A network composed solely of stations within mutual communication range of each
other via the wireless medium (WM). An ad hoc network is typically created in a
spontaneous manner. The principal distinguishing characteristic of an ad hoc
network is its limited temporal and spatial extent. These limitations allow the
act of creating and dissolving the ad hoc network to be sufficiently
straightforward and convenient so as to be achievable by nontechnical users of
the network facilities; i.e., no specialized "technical skills" are required
and little or no investment of time or additional resources is required beyond
the stations that are to participate in the ad hoc network. The term ad hoc is
often used as slang to refer to an independent basic service set (IBSS).

=== Association ===
The service used to establish access point/station (AP/STA) mapping and enable
STA invo-cation of the distribution system services (DSSs).

=== Authentication ===
The service used to establish the identity of one station as a member of the set
of stations authorized to associate with another station.

=== Basic service area (BSA) ===
The conceptual area within which members of a basic service set (BSS) may
communicate.

=== Basic service set (BSS) ===
A set of stations controlled by a single coordination function.

=== Basic service set (BSS) basic rate set ===
The set of data transfer rates that all the stations in a BSS will be
capable of using to receive frames from the wireless medium (WM). The BSS basic
rate set data rates are preset for all stations in the BSS.

=== Broadcast address ===
A unique multicast address that specifies all stations.

=== Channel ===
An instance of medium use for the purpose of passing protocol data units (PDUs)
that may be used simultaneously, in the same volume of space, with other
instances of medium use (on other channels) by other instances of the same
physical layer (PHY), with an acceptably low frame error ratio due to mutual
interference. Some PHYs provide only one channel, whereas others provide
multiple channels.

=== Clear channel assessment (CCA) function ===
That logical function in the physical layer (PHY) that determines the current
state of use of the wireless medium (WM).

=== Confidentiality ===
The property of information that is not made available or disclosed to
unauthorized individuals, entities, or processes.

=== Coordination function ===
The logical function that determines when a station operating within a basic
service set (BSS) is permitted to transmit and may be able to receive protocol
data units (PDUs) via the wire-less medium (WM). The coordination function
within a BSS may have one point coordination function (PCF) and will have one
distributed coordination function (DCF).

=== Coordination function pollable ===
A station able to (1) respond to a coordination function poll with a
data frame, if such a frame is queued and able to be generated, and (2)
interpret acknowledgments in frames sent to or from the point coordinator.

=== Deauthentication ===
The service that voids an existing authentication relationship.

=== Directed address ===
See: [wiki:Definizioni#Unicastframe Unicast frame].

=== Disassociation ===
The service that removes an existing association.

=== Distributed coordination function (DCF) ===
A class of coordination function where the same coordination function logic is
active in every station in the basic service set (BSS) whenever the network is
in operation.

=== Distribution ===
The service that, by using association information, delivers medium access
control (MAC) service data units (MSDUs) within the distribution system (DS).

=== Distribution system (DS) ===
A system used to interconnect a set of basic service sets (BSSs) and integrated
local area networks (LANs) to create an extended service set (ESS).

=== Distribution system medium (DSM) ===
The medium or set of media used by a distribution system (DS) for communications
between access points (APs) and portals of an extended service set (ESS).

=== Distribution system service (DSS) ===
The set of services provided by the distribution system (DS) that enable the
medium access control (MAC) to transport MAC service data units (MSDUs) between
stations that are not in direct communication with each other over a single
instance of the wireless medium (WM).[[BR]]
These services include transport of MSDUs between the access points (APs) of
basic service sets (BSSs) within an extended service set (ESS), transport of
MSDUs between portals and BSSs within an ESS, and transport of MSDUs between
stations in the same BSS in cases where the MSDU has a multicast or broad-cast
destination address or where the destination is an individual address, but the
station sending the MSDU chooses to involve DSS. DSSs are provided between pairs
of IEEE 802.11 MACs.

=== Extended rate set (ERS) ===
The set of data transfer rates supported by a station (if any) beyond the
extended service set (ESS) basic rate set. This set may include data transfer
rates that will be defined in future physical layer (PHY) standards.

=== Extended service area (ESA) ===
The conceptual area within which members of an extended service set
(ESS) may communicate. An ESA is larger than or equal to a basic service area
(BSA) and may involve several basic service sets (BSSs) in overlapping,
disjointed, or both configurations.

=== Extended service set (ESS) ===
A set of one or more interconnected basic service sets (BSSs) and inte-grated
local area networks (LANs) that appears as a single BSS to the logical link
control layer at any station associated with one of those BSSs.

=== Gaussian frequency shift keying (GFSK) ===
A modulation scheme in which the data is first filtered by a Gaussian filter in
the baseband and then modulated with a simple frequency modulation.

=== Independent basic service set (IBSS) ===
A BSS that forms a self-contained network, and in which no access to a
distribution system (DS) is available.

=== Infrastructure ===
The infrastructure includes the distribution system medium (DSM), access point
(AP), and portal entities. It is also the logical location of distribution and
integration service functions of an extended service set (ESS). An
infrastructure contains one or more APs and zero or more portals in addition
to the distribution system (DS).

=== Integration ===
The service that enables delivery of medium access control (MAC) service data
units (MSDUs) between the distribution system (DS) and an existing, non-IEEE
802.11 local area network (via a portal).

=== Medium access control (MAC) management protocol data unit (MMPDU) ===
The unit of data exchanged between two peer MAC entities to implement the MAC
management protocol.

=== Medium access control (MAC) protocol data unit (MPDU) ===
The unit of data exchanged between two peer MAC entities using the services of
the physical layer (PHY).

=== Medium access control (MAC) service data unit (MSDU) ===
Information that is delivered as a unit between MAC service access points
(SAPs).

=== Minimally conformant network ===
An IEEE 802.11 network in which two stations in a single basic service area
(BSA) are conformant with ISO/IEC 8802-11: 1999.

=== Mobile station ===
A type of station that uses network communications while in motion.

=== Multicast ===
A medium access control (MAC) address that has the group bit set. A multicast
MAC service data unit (MSDU) is one with a multicast destination address. A
multicast MAC protocol data unit (MPDU) or control frame is one with a multicast
receiver address.

=== Network allocation vector (NAV) ===
An indicator, maintained by each station, of time periods when transmission onto
the wireless medium (WM) will not be initiated by the station whether or not the
station’s clear channel assessment (CCA) function senses that the WM is busy.

=== Point coordination function (PCF) ===
A class of possible coordination functions in which the coordination function
logic is active in only one station in a basic service set (BSS) at any given
time that the network is in operation.

=== Portable station ===
A type of station that may be moved from location to location, but that only
uses net-work communications while at a fixed location.

=== Portal ===
The logical point at which medium access control (MAC) service data units
(MSDUs) from a non-IEEE 802.11 local area network (LAN) enter the distribution
system (DS) of an extended service set (ESS).

=== Privacy ===
The service used to prevent the content of messages from being read by other
than the intended recipients.

=== Reassociation ===
The service that enables an established association [between access point (AP)
and station (STA)] to be transferred from one AP to another (or the same) AP.

=== Station (STA) ===
 Any device that contains an IEEE 802.11 conformant medium access control (MAC)
and physical layer (PHY) interface to the wireless medium (WM).

=== Station basic rate ===
A data transfer rate belonging to the extended service set (ESS) basic rate set
that is used by a station for specific transmissions. The station basic rate may
change dynamically as frequently as each medium access control (MAC) protocol
data unit (MPDU) transmission attempt, based on local considerations at that
station.

=== Station service (SS) ===
The set of services that support transport of medium access control (MAC)
service data units (MSDUs) between stations within a basic service set (BSS).

=== Time unit (TU) ===
A measurement of time equal to 1024 µs.

=== Unauthorized disclosure ===
The process of making information available to unauthorized individuals,
entities, or processes.

=== Unauthorized resource use ===
Use of a resource not consistent with the defined security policy.

=== Unicast frame ===
A frame that is addressed to a single recipient, not a broadcast or multicast
frame. Syn: [wiki:Definizioni#Directedaddress Direct sddress].

=== Wired equivalent privacy (WEP) ===
The optional cryptographic confidentiality algorithm specified by IEEE 802.11
used to provide data confidentiality that is subjectively equivalent to the
confidentiality of a wired local area network (LAN) medium that does not employ
cryptographic techniques to enhance privacy.

=== Wireless medium (WM) ===
The medium used to implement the transfer of protocol data units (PDUs) between
peer physical layer (PHY) entities of a wireless local area network (LAN).

 ,,Copyright © 1999 IEEE. All rights reserved.,,