Is WiFi always backwards compatible?

Forums › LAN (ethernet/Wifi/routers/Bluetooth) › Is WiFi always backwards compatible?

Geektastic

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#309191 27-Sep-2023 17:24

We have a Grandstream WiFi network. There are three APs spread though the house.

Yesterday I did a firmware update on them. This morning our oldest iMac (2013) refused to use wireless at all despite showing it was connected.

I hooked it up with an Ethernet cable and it was absolutely fine.

Every other device in the house is fine on the WiFi.

I can’t find any obvious fault so I wondered if the firmware update might have done something that would prevent an older device from using it?

Linux

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#3135571 27-Sep-2023 17:27

A firmware update should not impact devices that have connected in the past

Behodar

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#3135573 27-Sep-2023 17:38

There have been some changes over the years (WEP, WPA, etc.) but I would've thought that a 2013 machine would be new enough to support all of them.

To isolate any software issues, try booting into recovery mode (Cmd-R at the boot chime) and see whether you can connect to Wi-Fi from there.

Batman

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#3135603 27-Sep-2023 18:45

always factory reset after doing a firmware update on a router or it can glitch to no end, every now and then, little bits here and there

but yeah i don't always follow my advice but this is the generic advice

Tinkerisk

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#3135616 27-Sep-2023 19:30

@geektastic

Just reboot the APs with power off/on and wait - they‘ll be back.

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Linux

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#3135619 27-Sep-2023 19:51

Have you removed the saved Wi-Fi network from the Mac?

timmmay

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#3135635 27-Sep-2023 20:32

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altered-ego
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#3135660 27-Sep-2023 22:19

Linux: Have you removed the saved Wi-Fi network from the MAC?

I'd start here. Easiest option.

For Wi-Fi encryption, you have Open < WEP < WPA < WPA2 < WPA3

You then also have TKIP vs. AES. TKIP is available on WEP & WPA. AES is the new kid & is supported from WPA onwards.

It is possible that the firmware upgrade either disabled WEP / WPA or changed from TKIP to AES. Removing / forgetting the network & joining again will connect with the correct encryption.

Other options get more involved. Often enough, even if you roll back the firmware of the WAP, it will not roll back from AES to TKIP.

Please keep this GZ community vibrant by contributing in a constructive & respectful manner.

BarTender

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#3135672 27-Sep-2023 23:01

Wireless protocols backward compatible.. No, not always.

Tinkerisk

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#3135693 28-Sep-2023 01:19

The is an option in the GWM’s config menu to stay „compatible to older wifi devices“ but usually, this is not modified during a f/w update. Check otherwise.

Jase2985

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#3135695 28-Sep-2023 03:51

hasnt switched to an incompatible wifi channel?

Geektastic

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#3135946 28-Sep-2023 14:14

I’ll work through all these. Thanks.

No other device using the same network has had any issues at all, just that one computer - which was 100% fine the day before.

The computer needs to go soon really - it won’t update to the new Mac OS versions and MS Office keeps complaining about that!