DEFINITIONS - 12

null data packet (NDP): A physical layer convergence procedure (PLCP) protocol data unit (PPDU) that
carries no Data field.
off-channel: Channel that is not the base channel.
operating channel: The operating channel is the channel used by the serving AP of the BSS to transmit
beacons. In an IBSS the operating channel is the channel used by the IBSS DFS owner to transmit beacons.
operating channel width: The channel width in which the station (STA) is currently able to receive.
overlapping basic service set (OBSS): A basic service set (BSS) operating on the same channel as the
station’s (STA’s) BSS and within (either partly or wholly) its basic service area (BSA).
over-the-air fast basic service set (BSS) transition (FT): An FT method in which the station (STA)
communicates over a WM link to the target access point (AP).
over-the-DS (distribution system) fast basic service set (BSS) transition (FT): An FT method in which
the station (STA) communicates with the target access point (AP) via the current AP.
pairwise: Referring to, or an attribute of, two entities that are associated with each other, e.g., an access
point (AP) and an associated station (STA), or two STAs in an independent basic service set (IBSS)
network. This term is used to refer to a type of encryption key hierarchy pertaining to keys shared by only
two entities.
pairwise master key (PMK): The key derived from a key generated by an Extensible Authentication
Protocol (EAP) method or obtained directly from a preshared key (PSK).
pairwise master key R0 (PMK-R0): The key at the first level of the fast basic service set (BSS) transition
(FT) key hierarchy.
pairwise master key (PMK) R0 name (PMKR0Name): An identifier that names the PMK-R0.
pairwise master key (PMK) R0 key holder identifier (R0KH-ID): An identifier that names the holder of
the PMK-R0 in the Authenticator.
pairwise master key R1 (PMK-R1): A key at the second level of the fast basic service set (BSS) transition
(FT) key hierarchy.
pairwise master key (PMK) R1 name (PMKR1Name): An identifier that names a PMK-R1.
pairwise master key (PMK) R1 key holder identifier (R1KH-ID): An identifier that names the holder of
a PMK-R1 in the Authenticator.
pairwise master key (PMK) S0 key holder identifier (S0KH-ID): An identifier that names the holder of
the PMK-R0 in the Supplicant.
pairwise master key (PMK) S1 key holder identifier (S1KH-ID): An identifier that names the holder of
the PMK-R1 in the Supplicant.
pairwise transient key (PTK): A concatenation of session keys derived from the pairwise master key
(PMK) or from the PMK-R1. Its components include a key confirmation key (KCK), a key encryption key
(KEK), and one or more temporal keys that are used to protect information exchanged over the link.
pairwise transient key (PTK) name (PTKName): An identifier that names the PTK.