Wednesday, October 11, 2017

Attempts to fix 802.11ac WiFi networking issues

My boss and I have been dealing with WiFi issues in regards to various home & work situations. I've been trying to assemble a good strategy to deal with them, and there appears to be some promising leads.

  • 802.11ac environments, you have 5ghz available, as well as 2.4ghz. However, it turns out that "Dynamic Frequency Selection" is eager to not interfere with radar installations. Per a chart of 802.11 5ghz channels, that's channels 100-149 to avoid using in a major urban area; so I am currently not using that + have DFS turned off. Use a good WiFi analyzer app to pick the least used channel outside that range.
  • If you're supporting older iPhones for people, it may not like 40mhz 2.4ghz setups; found multiple posts online about that. Keep your 2.4ghz to 20mhz; and also to N-only mode if you've managed to ditch all your old B & G devices.
  • In a residential setting, turn the power down. And if you know your neighbors, ask them to as well. 50-75% should be fine; especially in an apartment complex.
  • I set my Fragmentation Threshold to 1500, and RTS Threshold to 1501 for now. I need to study these more, but your standard Ethernet framing isn't more than 1500 anyway; and I've read that in congested areas, "less is more".
  • I also read that if your devices aren't going to be switching SSIDs a lot, to try raising the DTIM above the default of 1 (2 or 3 seem to be valid), and/or raise your Beacon Interval past 100 (currently set mine at 3000). This is supposed to keep your wireless devices from waking up too much, and draining power. However, too high of a the settings are said to negatively impact realtime chat + video apps.
Added: good, but dense, eBook on this stuff

Added#2: some more suggested tweaking on the Frag/RTS setting. I'm trying 1312 for my settings now, since I do have IPv6 on my connection (1280 bytes +34 byte MAC header).