Reduced Interframe Space (RIFS) is one of the new features introduced in IEEE 802.11n to improve its efficiency. RIFS is the time in micro seconds by which the multiple transmissions from a single station are separated. RIFS is used when no SIFS separated response frames are expected from the receiver. The value of RIFS is 2μs for 802.11n phy.
The use of RIFS is obsolete from 802.11ac amendment onwards.
An 802.11ac station will not transmit frames separated by RIFS. So a 11ac station operating in HT mode sets the RIFS mode field in HT operation element to 0.
See also
* SIFS -
Short Interframe Space
Short Interframe Space (SIFS), is the amount of time in microseconds required for a wireless interface to process a received frame and to respond with a response frame. It is the difference in time between the first symbol of the response fra ...
* PIFS -
PCF Interframe Space
Point coordination function (PCF) is a media access control (MAC) technique used in IEEE 802.11 based WLANs, including Wi-Fi. It resides in a point coordinator also known as access point (AP), to coordinate the communication within the network. ...
* DIFS -
DCF Interframe Space The IEEE 802.11 family of standards describe the DCF protocol, which controls access to the physical medium. A station must sense the status of the wireless medium before transmitting. If it finds that the medium is continuously idle for DCF Inter ...
* AIFS -
Arbitration Interframe Space
* PCF -
Point Coordination Function
Point coordination function (PCF) is a media access control (MAC) technique used in IEEE 802.11 based WLANs, including Wi-Fi. It resides in a point coordinator also known as access point (AP), to coordinate the communication within the network. ...
References
{{IEEE standards
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