NOTE: this page is for archival only, see the note at the end of the page.

iw

  • implement "scan" command that triggers, waits and dumps

cfg80211

  • configuration API

  • make nl80211/cfg80211 (and mac80211 where it is involved) have generation numbers for all dumps so that userspace can tell whether it got a proper snapshot dump or not
  • use 802.11 MLME SAP interface where appropriate
  • validate channel setting vs. all virtual interfaces

mac80211

important

  • integrate rfkill support into mac80211's radio_enabled flag
  • explain rate[i].retry in TX status with examples

AP support

  • fix the PS filtering code: document that hardware may never unset the filter for a station unless instructed to, use the pending queue, remove ieee80211_remove_tx_extra
  • injected frames need to be tied to another virtual interface to get the software sequence number and keys (only relevant for 11w) right
  • internal bridge setting (separated STAs in the BSS)
  • Radar detection (AP DFS or 802.11h)

Needing investigation

  • see how the default QoS parameters should be set up
  • see if QoS parameters should be reset to defaults when disassociating

Long term

  • hide (or get rid of) master dev

Issues

  • handle reassociation when the AP is out of range for a moment and then comes back
  • Need to stop TX/RX when a radar is detected for the duration of scan for a new channel. [reported by Jouni Malinen]

power saving

  • support pm_qos
  • u-APSD support. Intel has old AP u-APSD patches (incomplete, buffering is done in their firmware)

Roaming

mac80211 drivers use wpa_supplicant for help with Roaming. This is done by specifying ap_scan=1, which lets wpa_supplicant select the BSS based on scan results. This works but it could use some more enhancements.

To have better roaming we need to enhance background scanning. We can either enhance the kernel mac80211 STA MLME or userspace MLME. A quicker/temporary solution can be to have wpa_supplicant request scans periodically.

Misc

  • Add dormant state support.
  • Export more hardware capabilities as wiphy attribute via nl80211 (is anything missing now?)
  • Kicking DMA on the last fragment only (?) [suggested by Ivo van Doorn]
  • In case of STA or IBSS, after a change of SSID or generic_element, ieee80211_if_conf should be called.
  • Try to switch from sw crypto to hw when there was no more room for STA keys in the hardware and one STA disassociates (so there is possibly a room now). [suggested by Johannes and Michael]

Optimizations

  • ieee80211_get_hdrlen and ieee80211_is_eapol are called very often.
  • Recognition of device incoming frame belongs to can be made much smarter and faster.
  • think about handling probe responses in firmware like b43 can. This requires telling hostapd that it shouldn't be replying to probe requests and having it give the appropriate info to the kernel [Johannes/Michael]
  • Order available BSSes by rssi in STA/IBSS mode. We do this in ieee80211_rx_bss_add() ieee80211_sta.c

Wishlist

  • Add #ifdef's for not compiling AP stuff. [suggested by Jouni Malinen]
  • keep track of stations per virtual interface, helps with the optimisation asked for above

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