4.3.11 STA transmission of data frames outside the context of a BSS

4.3.11 STA transmission of data frames outside the context of a BSS

In addition to defining procedures for STA communication within a BSS, this standard also allows a STA
that is not a member of a BSS to transmit data frames. Such data frames are defined as being transmitted
outside the context of a BSS. A STA transmits a data frame outside the context of a BSS only if
dot11OCBActivated is true.
NOTE—The specific frame subtypes that a STA is allowed to send when it has dot11OCBActivated true are specified in
10.20.
When dot11OCBActivated is true, a data frame can be sent to either an individual or a group destination
MAC address. This type of communication is only possible between STAs that are able to communicate
directly over the wireless medium. It allows immediate communication, avoiding the latency associated with
establishing a BSS. When dot11OCBActivated is true, a STA is not a member of a BSS and it does not
utilize the IEEE 802.11 authentication, association, or data confidentiality services. This capability is
particularly well-suited for use in rapidly varying communication environments such as those involving
mobile STAs in which the interval over which the communication exchanges take place may be of very
short-duration (e.g., on the order of tens or hundreds of milliseconds). Since IEEE 802.11 MAC sublayer
authentication services are not used when dot11OCBActivated is true, any required authentication services
are provided by the station management entity (SME) or by applications outside of the MAC sublayer.
A STA whose MIB does not include the dot11OCBActivated attribute operates as if the attribute is false.
Communication of data frames when dot11OCBActivated is true might take place in a frequency band that
is dedicated for its use, and such a band might require licensing depending on the regulatory domain. A STA
for which dot11OCBActivated is true initially transmits and receives on a channel known in advance, either
through regulatory designation or some other out-of-band communication. A STA’s SME determines PHY
layer parameters, as well as any changes in the operating channel, e.g., using information obtained via outof-
band communication or over-the-air frame exchange. When dot11OCBActivated is true, a sending STA
sets the BSSID field to the wildcard BSSID value (see 8.2.4.3.4).

The Vendor Specific frame (see 8.5.6) provides one means for STAs to exchange management information
prior to communicating data frames outside the context of a BSS.