PCF Interframe Space

PCF Interframe Space: PCF Interframe Space (PIFS) is one of the interframe space used in IEEE 802.11 based Wireless LANs. PCF enabled access point wait for PIFS duration rather than DIFS to occupy the wireless medium. PIFS duration is less than DIFS and greater than SIFS (DIFS > PIFS > SIFS). Hence AP always has more priority to access the medium.

PIFS duration can be calculated as follows:

PIFS = SIFS + Slot time ^[1]

Standard Slot time (us) PIFS (us)

IEEE 802.11b 20 30

IEEE 802.11a 9 25

IEEE 802.11g 9 or 20 19 or 30

See also

DIFS

SIFS

AIFS

RIFS

EIFS

Point Coordination Function

References

^ "IEEE 802.11-2007 Standard". http://standards.ieee.org/getieee802/download/802.11-2007.pdf.

Categories:
IEEE 802.11

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Short Interframe Space — (SIFS), is the small gap between the data frame and its acknowledgment. SIFS are found in IEEE 802.11 networks. They are used for the highest priority transmissions enabling stations with this type of information to access the radio link first.… … Wikipedia
DIFS — DCF Interframe Space (DIFS) is a period of time for which a station waits after it has found the channel idle. In the DCF protocol defined by IEEE 802.11 wireless LAN standard at the MAC sublayer, a station senses the medium when it wants to… … Wikipedia
AIFS — abbr. Arbitrary InterFrame Space (MAC, PCF, IFS, WLAN) … United dictionary of abbreviations and acronyms
EIFS — abbr. Extended InterFrame Space (MAC, PCF, IFS, WLAN) … United dictionary of abbreviations and acronyms
PIFS — abbr. Point Coordination Function InterFrame Space (MAC, 802.11a, PCF, IFS, WLAN) … United dictionary of abbreviations and acronyms

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