Help Getting to the 300 or 450Mbps Speed

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Nismo

[H]ard|Gawd
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Mar 10, 2000
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I've got a Linksys 4200v2 with a laptop client that has an Intel 5300 with 3 antenna. I am trying to get to the 300 or 450mbps speeds, but can't seem to do it.

I seem to be able to get 217Mbps on both the 2.4 and 5 GHz bands. Does this seem to be a NON-bonded speed? How do I enable bonded speeds?

Here is what is wierd, when I enable 40MHz Channel width on teh 5GHz band, the laptop cannot connect. If I drop it down to 20MHz, it will connect.

What are the settings I need to reach 300 or 450mbps speeds? Or am I not reaching it because there are other networks around me?

Thanks for the help.
 
How are you getting the 217 Mb measurement? Is this real world throughput based on testing or reported port speed?

The 300 - 450 Mbps is not real world throughput. If I remember the reviews correctly, about 100Mbps is the best you'll acheive at 3 stream 450Mb wireless
 
I am aware of that, this is just the reported connection in windows. I'd like to connect at the fastest I can though. I know the card and router can do 450mbps, but the most I can get is 217. I should at least be able to get 300.

Does the 2.4 and 5GHz band need to be set with the same settings? I mean, do they use each others bandwidth to achieve 300 or 450Mbps?
 
Nismo said:
I am aware of that, this is just the reported connection in windows. I'd like to connect at the fastest I can though. I know the card and router can do 450mbps, but the most I can get is 217. I should at least be able to get 300.

Does the 2.4 and 5GHz band need to be set with the same settings? I mean, do they use each others bandwidth to achieve 300 or 450Mbps?
Click to expand...

It can just depend on many factors , are you checking to make sure you aren't using any channels others are? Are you using 2.4Ghz or 5Ghz to attempt to achieve this?

Are you sure your router has 40mhz enabled for both of those frequencies? Even under ideal conditions sometimes Wifi just doesn't perform like it should. Its crazy that they can advertise silly things like "450Mbps transfer speed!" or now they combine the 2.4 and 5Ghz frequencies max theoretical throughput and say "900Mbps total!!!".

Its odd that it won't connect if you enable 40mhz on the 5Ghz frequency , although the Version 2 of that Linksys 4200 router should be able to connect properly...
 
Understand that when you're using 40 MHz frequencies, you're covering a ridiculous amount of the 2.4 GHz band. You're stretching across multiple channels and introducing even more opportunity for packet collisions with other nearby 2.4 GHz access points because you're more likely than not to be overlapping channels. With 20 MHz frequencies, you overlap with the adjacent 4 channels on either side (hence why we commonly use channels 1, 6, and 11). With 40 MHz frequencies, you overlap the adjacent 8 channels, and can't even use a few of the lower and higher channels because you would overlap into registered spectrum.

In short, overlapping channels means you're basically sharing the available bandwidth of that spectrum with someone else. This is why using 40 MHz channels is really only a good idea in the much-less-crowded 5 GHz spectrum.

On top of that, collisions mean retransmits which waste bandwidth, and 802.11n has some significant protocol overhead as well. Consider that the 802.11g protocol, due to error correction and headers, delivered only on average about 22 Mbps actual data throughput, of that promised "total" 54 Mbps.

Wireless N isn't that much better; expect to see roughly half of your "total" bandwidth in actual data throughput. 217 Mbps actually sounds about right!
 
Electrofreak said:
Understand that when you're using 40 MHz frequencies, you're covering a ridiculous amount of the 2.4 GHz band. You're stretching across multiple channels and introducing even more opportunity for packet collisions with other nearby 2.4 GHz access points because you're more likely than not to be overlapping channels. With 20 MHz frequencies, you overlap with the adjacent 4 channels on either side (hence why we commonly use channels 1, 6, and 11). With 40 MHz frequencies, you overlap the adjacent 8 channels, and can't even use a few of the lower and higher channels because you would overlap into registered spectrum.

In short, overlapping channels means you're basically sharing the available bandwidth of that spectrum with someone else. This is why using 40 MHz channels is really only a good idea in the much-less-crowded 5 GHz spectrum.

On top of that, collisions mean retransmits which waste bandwidth, and 802.11n has some significant protocol overhead as well. Consider that the 802.11g protocol, due to error correction and headers, delivered only on average about 22 Mbps actual data throughput, of that promised "total" 54 Mbps.

Wireless N isn't that much better; expect to see roughly half of your "total" bandwidth in actual data throughput. 217 Mbps actually sounds about right!
Click to expand...

Wireless speed has always been about half of your actual windows connect speed. But that would mean I am connecting on windows at 450Mbps, and actually using a tool to measure the 217Mbps. That is no the case. I am getting 217Mbps in windows, but that probably equates to well under 100Mbps in a real life measurement.

The strange part is, I cannot get my Intel 5300 to connect at 40MHz on 5GHz. (Intel says it does support this.)
 
Nismo said:
Wireless speed has always been about half of your actual windows connect speed. But that would mean I am connecting on windows at 450Mbps, and actually using a tool to measure the 217Mbps. That is no the case. I am getting 217Mbps in windows, but that probably equates to well under 100Mbps in a real life measurement.

The strange part is, I cannot get my Intel 5300 to connect at 40MHz on 5GHz. (Intel says it does support this.)
Click to expand...

Oh, I see, your current negotiated data rate is 217 Mbps; I figured you were throwing a file across the WLAN and reading the transfer speed or some such.
 
The negotiated rate is not a 'data' rate. It is a radio rate. With retransmits, other overhead, etc, you will not achieve anywhere near that radio rate for a data speed.

I've never had a client negotiate at 450mbps. I'm not saying it can't be done but it just hasn't happened for me.
 
You'll never see 450 with a single device.

450mbps is the total bandwidth available on the router of both 2.4ghz and 5ghz used that the same time.

In theory you can connect at 300mbps using channel bonding on 2.4ghz.

That means you are standing less than 10' from the router with no obstructions, no background 2.4 ghz noise in the area, both the router and your wireless card need to be the same chipset AND you have sacrificed the sacred cow to the wireless Gods.

From a marketing point of view, this is similar to the Jensen branded stereo sold at K-mart for $29.99 that features a 1000 watt amp.
 
Eickst said:
The negotiated rate is not a 'data' rate. It is a radio rate. With retransmits, other overhead, etc, you will not achieve anywhere near that radio rate for a data speed...
Click to expand...

Yeah... that's exactly what I wrote earlier, check up a few posts. :p

The term for the speed that the wireless adapter negotiates with the access point actually is "data rate". We all know that data throughput (which I think is the term you're looking for) is much less, typically about half, of the data rate.
 
40Mhz is bad, dont use it, your going to cause issues with wireless around you according to this guy

http://www.smallnetbuilder.com/wire...6-it-takes-a-neighborhood-to-fix-bad-wireless
Wide mode

802.11n routers have what is called 40 MHz (wide mode) and one neighbor had it enabled. What Wide mode basically does is occupy a second channel to theoretically double your throughput. Out in the boonies this would be great. But in a crowded neighborhood, it can actually slow you down and take away available channels for your neighbors. Be sure that you have wide mode set to off, or 20 Mhz mode. Pictured is how to do it on one type of router, yours may be slightly different.
Click to expand...
 
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