Arbitration inter-frame spacing (AIFS), in
wireless LAN
A wireless LAN (WLAN) is a wireless computer network that links two or more devices using wireless communication to form a local area network (LAN) within a limited area such as a home, school, computer laboratory, campus, or office building ...
communications, is a method of prioritizing one Access Category (AC) over the other, such as giving voice or video priority over email. AIFS functions by shortening or expanding the period a wireless node has to wait before it is allowed to transmit its next frame. A shorter AIFS period means a message has a higher probability of being transmitted with low latency, which is particularly important for delay-critical data such as voice or streaming video.
AIFS is a time interval between frames being transmitted under the IEEE
802.11e
IEEE 802.11e-2005 or 802.11e is an approved amendment to the IEEE 802.11 standard that defines a set of quality of service (QoS) enhancements for wireless LAN applications through modifications to the media access control (MAC) layer.M. Benven ...
EDCA MAC
Mac or MAC most commonly refers to:
* Mac (computer), a family of personal computers made by Apple Inc.
* Mackintosh, a raincoat made of rubberized cloth
* A variant of the word macaroni, mostly used in the name of the dish mac and cheese
* Mac, ...
. It depends on the Access Category and generally depends on the AIFSN, or AIFS-number. AIFS is defined by the formula AIFSN
C* ST + SIFS, where the AIFSN depends on the Access Category. Slot time ST (also denoted by
) is dependent on the physical layer.
Short Interframe Space (SIFS) is the time between a DATA and ACK frame.
AIFSN
Cwill be set by the AP in the EDCA Parameter set in beacon and probe response frames. If it is not set then the STA has to use the default values.
The IEEE
802.11e
IEEE 802.11e-2005 or 802.11e is an approved amendment to the IEEE 802.11 standard that defines a set of quality of service (QoS) enhancements for wireless LAN applications through modifications to the media access control (MAC) layer.M. Benven ...
EDCA MAC has been adopted as part of the IEEE
802.11p standard for Wireless Access in Vehicular Environments (WAVE).
IEEE 802.11
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