Indicated the number of octets in an MPDU,
below which an RTS/CTS handshake is not performed. An
RTS/CTS handshake is performed at the beginning of any
frame exchange sequence where the MPDU is of type Data or
Management, the MPDU has an individual address in the Address1
field, and the length of the MPDU is greater than
this threshold. (For additional details, refer to Table 21 in
9.7.) Setting this attribute to be larger than the maximum
MSDU size has the effect of turning off the RTS/CTS
handshake for frames of Data or Management type transmitted by
this STA. The default value of this attribute is 2347.