20Mhz/40Mhz channels and a Mac/ethernet limiting speed

Ol!ver · 16 Feb 2012 at 00:33

Morning!

I bought a TP-Link WA901ND access point, which is a 300Mbps device which uses the 20Mhz and 40Mhz channels. The problem is it only connects at 130Mhz when using a Mac because Apple limited the WiFi card's driver. Apparently the 40Mhz setting can affect bluetooth.

Anyway, this all got me wondering....

The access point itself has a 100Mbps ethernet port on the back. Will that not limit the throughput no matter how fast the WiFi runs, or am I being a bit dim?

Ol!ver · 16 Feb 2012 at 08:11

Tealc said:
You'd be lucky to see anywhere near the theoretical maximum 300 Mbps over a wireless link anyway, it'll be more like 70-100 Mbps which won't be bottlenecked by the incoming ethernet connection.

Any idea what the actual throughput of a 100Mbps connection is compared to a 300Mbps WiFi connection?

To add to the fun, I've got half the network on a 200Mbps HomePlug system, too.

What I've noticed is that I get the same speeds whether I use WiFi or wired when transferring over the HomePlugs - about 5MB/s.

Ol!ver · 16 Feb 2012 at 08:29

pyropetepete said:
Just had the same issue, its the Intel WIFI card!

Change the settings on it all to high and it will then run @ 300mbps down, 150mbps up.

It's an Intel card i bet!

TP only allows a mix of 20/40 or 20. 20 doesn't allow 300mbps

It's a MacBook and a MacBook Air - Apple's own hardware made by Nvidia I think. Either way, it's definitely the OS X driver that limits it.

Ol!ver · 16 Feb 2012 at 10:16

SeeKified said:
40MHz channels should only be used on 5GHz as it cripples the 2.4GHz spectrum. Do your MacBooks support 5GHz? If not, you won't be seeing 300Mbps.

The Macs do support 5GHz, but the AP does not.

Just done some speed tests because I'm now apparently a little OCD about the whole thing!

http://simp.ly/publish/b26kpS

Turns out one of my extensions is a bit crap.

Ol!ver · 16 Feb 2012 at 11:16

pyropetepete said:
Nah i belive it's Intel on the wifi as there Intel bassed systems and Nvidia doesn't have anyhting wifi listed

Yeah, think you're right.

Anyone got any thoughts on my results in the link above?

Ol!ver · 16 Feb 2012 at 11:21

Sin_Chase said:
Some Intel cards refuse to do N speeds unless WMM is enabled, they are very fussy about what type of encryption you use also.

WMM is on, no WEP - MAC filtering only.

Ol!ver · 16 Feb 2012 at 12:39

I think that basically what I'm trying to work out is what the bottleneck is - the HomePlugs, the WiFi or the 100Mbps switch that's in the Sky router.

I'm also confused about these 200Mbps HomePlugs having 100Mbps ethernet ports.

Ol!ver · 16 Feb 2012 at 12:57

I've read reviews of 500Mbps HomePlugs hitting 55MB/s, which sounds a lot considering the speeds expected from Gigabit.

Ol!ver · 16 Feb 2012 at 13:16

pyropetepete said:
Ol!ive - can you list what the parts are exactly, how there setup.

I just been at a clients with 200mbps TP-Link homeplugs and he had them in the wrong locations

Okey dokey.

Sky router as the switch. Off that we have one of the HomePlugs http://www.tp-link.com/en/products/details/?categoryid=1862&model=TL-PA211 and a TP-Link AP http://www.tp-link.com/en/products/details/?categoryid=239&model=TL-WA901ND

The other end of the HomePlug is upstairs with just a file server attached.

There are the usual PS3/360/Apple TV/Sky HD box connected to the Sky router over WiFi and Ethernet.

Ol!ver · 19 Feb 2012 at 00:29

pyropetepete said:
What is the reason for the AP by the way?

AP in the Sky router is 11g.