Back in 1993 you had to compile the Linux kernel from source and modules were not invented yet. But we had this amazing kernel configure script to set things up. If somebody claims to be in the networking business for a long time, ask him which number comes to mind when you say 3Com (correct answer: 3c509, wrong answer: Is that a Telko?). Getting your 3Com adapter to work with Linux was easy. But then came this wireless stuff…closed source drivers…reverse engineering…NDIS Wrapper…

Unfortunately now, many many years later, this “wireless stuff” is still a big source of problems on linux. Power save mode killing your connections (Ralink) or drivers that you cannot compile anymore on 4.x kernels (Realtek). While on Windows, this hardware just works…

Then there is the user-land software: iwconfig, wpa_supplicant, connman, Network Manager etc., configuring a Win 2012R2 server is more fun. Not to mention the many (often conflicting) opinions about configuring your wireless adapter.

Back to basics: you only need wpa_supplicant, wireless tools (iwconfig etc.) and maybe some firmware, depending on your adapter. That’s all, apart from the right kernel support/module, buts that’s not user-land. Conman, Network Manager, etc.  all run “on top” of these tools and are for your convenience only.

Throughput

Then you have the wireless protocol itself. On a 300 mbps link (MCS 15) you get much lower real throughput. Yes that’s the wireless overhead, as explained rather poorly here. The guys at FlexRadio do a better job explaining. They assume that since the link is half-duplex, max. speed is cut in half. That is only true if the timing is fixed, which it is not. This presentation explains the details.

Linksys

After struggling with USB Wlan adapters on my BeagleBone Black, I decided to reuse my good old WRT-54GS. It still had the DD-WRT firmware (from 2010) on it and after some config, I started to use it. Only 802.11g with a real throughput of about 17 Mbps (speedtest). But is low throughput always a bad thing? Well, only if you plan to download a lot… In my case, streaming audio over the internet, the WRT-54GS performance is perfect. And the irregular delays I got on RDP are gone. This ancient router still beats the competition, especially when it comes to looks…

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