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    iwlwifi: Use RTS/CTS as the preferred protection mechanism for 6000 series · 47eef9bd
    Wey-Yi Guy 提交于
    When 802.11g was introduced, we had RTS/CTS and CTS-to-Self protection
    mechanisms. In an HT Beacon, HT stations use the "Operating Mode" field
    in the HT Information Element to determine whether or not to use
    protection.
    
    The Operating Mode field has 4 possible settings: 0-3:
    Mode 0: If all stations in the BSS are 20/40 MHz HT capable, or if the
    BSS is 20/40 MHz capable, or if all stations in the BSS are 20 MHz HT
    stations in a 20 MHz BSS
    Mode 1: used if there are non-HT stations or APs using the primary or
    secondary channels
    Mode 2: if only HT stations are associated in the BSS and at least one
    20 MHz HT station is associated.
    Mode 3: used if one or more non-HT stations are associated in the BSS.
    
    When in operating modes 1 or 3, and the Use_Protection field is 1 in the
    Beacon's ERP IE, all HT transmissions must be protected using RTS/CTS or
    CTS-to-Self.
    
    By default, CTS-to-self is the preferred protection mechanism for less
    overhead and higher throughput; but using the full RTS/CTS will better
    protect the inner exchange from interference, especially in
    highly-congested environment.
    
    For 6000 series WIFI NIC, RTS/CTS protection mechanism is the
    recommended choice for HT traffic based on the HW design.
    Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>
    Signed-off-by: NReinette Chatre <reinette.chatre@intel.com>
    Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
    47eef9bd
iwl-core.h 24.2 KB