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Wireless Multimedia Extensions (WME), also known as Wi-Fi Multimedia (WMM), is a Wi-Fi Alliance interoperability certification, based on the IEEE 802.11e standard. It provides basic Quality of service (QoS) features to IEEE 802.11 networks. WMM prioritizes traffic according to four Access Categories (AC): voice (AC_VO), video (AC_VI), best effort (AC_BE), and background (AC_BK). However, it does not provide guaranteed throughput. It is suitable for well-defined applications that require QoS, such as Voice over IP (VoIP) on Wi-Fi phones (VoWLAN).

WMM replaces the Wi-Fi DCF distributed coordination function for CSMA/CA wireless frame transmission with Enhanced Distributed Coordination Function (EDCF). EDCF, according to version 1.1 of the WMM specifications by the Wi-Fi Alliance, defines Access Categories labels AC_VO, AC_VI, AC_BE, and AC_BK for the Enhanced Distributed Channel Access (EDCA) parameters that are used by a WMM-enabled station to control how long it sets its Transmission Opportunity (TXOP), according to the information transmitted by the access point to the station. It is implemented for wireless QoS between RF media.

Power Save Certification

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The Wi-Fi Alliance has added Power Save Certification to the WMM specification. Power Save uses mechanisms from 802.11e and legacy 802.11 to save power (for battery powered equipment) and fine-tune power consumption. The certification provides an indication that the certified product is targeted for power critical applications like smart phones and portable power devices (i.e. those that require battery or recharging such as smart phones.)

The underlying concept of WMM PowerSave is that the station (STA) triggers the release of buffered data from the access point (AP) by sending an uplink data frame. Upon receipt of such a data (trigger) frame the AP releases previously buffered data stored in each of its queues. Queues may be configured to be trigger-enabled, (i.e. a receipt of a data frame corresponding to the queue acts as trigger), and delivery enabled, (i.e. data stored at those queues will be released upon receipt of a frame). Queues refer to the four ACs defined for WMM.

See also

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WMM

video editing software package, and file format extension Wi-Fi Multimedia or Wireless Multimedia Extensions (WME), a QoS implementation Women Make Movies

Wi-Fi Alliance

Multiband, and Optimized Connectivity. Wi-Fi Multimedia (WMM) or known as Wireless Multimedia Extensions is a Wi-Fi Alliance interoperability certification

Ralink

have also been selected in the Wi-Fi Protected Setup (WPS) and Wireless Multimedia Extensions Power Save (WMM-PS) testbeds. Ralink was a participant in the

Collision domain

problem for a collision domain. This technique is employed by Wireless Multimedia Extensions. Point coordination function and distributed coordination function

SIP extensions for the IP Multimedia Subsystem

capabilities and extensions in SIP while, in other cases, the 3GPP had to collaborate with the IETF to standardize new SIP extensions to meet the new requirements

IEEE 802.11r-2008

including 802.11i with 802.1X authentication and 802.11e (QoS) or Wireless Multimedia Extensions (WMM) with admission control requests, the number of messages

IP Multimedia Subsystem

standardize applications, but rather to aid the access of multimedia and voice applications from wireless and wireline terminals, i.e., to create a form of fixed-mobile

MMX (instruction set)

Intel and others: 3DNow!, Streaming SIMD Extensions (SSE), and ongoing revisions of Advanced Vector Extensions (AVX). MMX is officially a meaningless initialism