My wi-fi connection randomly disconnects and I see these messages in kernel log: [ter mai 11 04:05:15 2021] wlan0: deauthenticated from <MAC address> (Reason: 7=CLASS3_FRAME_FROM_NONASSOC_STA) [ter mai 11 04:05:15 2021] audit: type=1130 audit(1620716716.140:174): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=NetworkManager-dispatcher comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success' [ter mai 11 04:05:15 2021] wlan0: authenticate with <MAC address> [ter mai 11 04:05:15 2021] wlan0: send auth to <MAC address> (try 1/3) [ter mai 11 04:05:15 2021] wlan0: authenticated [ter mai 11 04:05:15 2021] wlan0: associate with <MAC address> (try 1/3) [ter mai 11 04:05:15 2021] wlan0: RX AssocResp from <MAC address> (capab=0x1401 status=0 aid=1) [ter mai 11 04:05:15 2021] wlan0: associated [ter mai 11 04:05:15 2021] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready [ter mai 11 04:05:28 2021] audit: type=1131 audit(1620716728.750:175): pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=NetworkManager-dispatcher comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success' Currently I use kernel 5.12.2-arch1-1 on Arch Linux but the problem also occurs with linux-lts 5.10.34-1. Random disconnections persist even when wi-fi authentication is disabled in the settings page of my internet router. I also have replaced Network Manager with netctl on my system but nothing changed. I use and old Lenovo G400S Touch laptop with this wi-fi adapter: 02:00.0 Network controller: Intel Corporation Centrino Wireless-N 135 (rev c4) Subsystem: Intel Corporation Centrino Wireless-N 135 BGN Kernel driver in use: iwlwifi Kernel modules: iwlwifi Power management of the wi-fi adapter is off: wlan0 IEEE 802.11 ESSID:"SSID" Mode:Managed Frequency:2.427 GHz Access Point: <MAC adress> Bit Rate=65 Mb/s Tx-Power=15 dBm Retry short limit:7 RTS thr:off Fragment thr:off Power Management:off Link Quality=70/70 Signal level=-35 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Other things that I tried to stop random wi-fi disconnections: changed wi-fi mode from B+G+N to just G and then to just N; specified a channel in the settings of internet router instead of using automatic mode; congigured the wi-fi regulatory domain on my system to my country; configured MAC address of my internet router as BSSID in the settings of my wi-fi connection; changed autenthication method in internet router settings from default WPA/WPA2-PSK + TKIP/AES to WPA2-PSK + AES; replaced internal dhcp client of Network Manager with dclient; disabled MAC randomization in Network Manager; disabled "Protected 802.11n" feature in internet router; added the following line to /etc/modprobe.d/iwlwifi.conf file: options iwlwifi swcrypto=1 11n_disable=1