Acronym soup is the result of an over-zealous use of abbreviations (OZUOA). Written with a sufficient density, the effect of Acronyms can overpower a reader, resulting in total brain shutdown (TBS) and inhibited learning syndrome (ILS). Here is an example courtesy '802.11 Wireless LAN Fundamentals' by Roshan & Leary.
The Contention Free Period (CFP) is the window of time for PCF operation. The CFP begins at set intervals following a beacon time frame containing a delivery traffic indication map (DTIM) information element. The Frequency of CFPs is determined by the network administrator. Once the CFP begins, the AP assumes the role of PC (and as such, PCF operation is only supported in infrastructure BSSs). Each 802.11 client sets its NAV to the CFPMaxDuration value. This value is included in the CF parameter set information element. The CFPMaxDuration defines the time value that is the maximum duration for the CFP. The PC can end the CFP before the CFPMaxDuration time elapses. The AP transmits beacon frames at regular intervals, and beacon frames sent during the CFP contain the CFPDurationRemaining field to update station NAVs of the remaining duration of the CFP. Figure 2015 depicts the CFP and CP as a function of time.