Intel Pro 4965 agn mini PCI adapter and wireless N speed

[Jim K]

I have a Netgear WNR854T (Gigabit Wireless N Access Point / Switch / Router) with latest firmware (Ver. 1.4.23.NA) and the Intel Pro 4965 agn mini PCI adapter in my x61s... after setting up the access point and client computer with WPA2-PSK, I am able to connect at 144mbps on the x61s... not bad, however, I have another laptop with a Netgear WN511T pc card, and it connects at 300mbps to the access point.

This seems to indicate that the x61s is connecting with 20MHz bonded channels, and the WN511T is connecting with 40MHz bonded channels... can anyone shed any light on what the problem is, or better yet, what the solution is?

[SHoTTa35]

Oh, hmm.. did your system come with N installed or did you install it yourself? If you installed it yourself do you have all 3 antenna's connected? In order to operate in 40mhz mode you need 3 antenna's. 1 each for 20mhz receive but 1 in 20mhz for send. MIMO

[Jim K]

yes, Intel Pro 4965 agn card is factory built-in, and there should be triple antennas built in as I interpret the factory build sheet... and there's no reason they shouldn't be, when you look at the area used by the Netgear card for it's antennas; the range of Netgear's card is super compared to abg wi fi!

[f00kie]

Intel 4965agn only does 40Mhz channels in the 5.8Ghz frequency, not 2.4Ghz, which is why you're seeing 130Mbps/144Mbps. Plus, these link speeds mean absolutely nothing in terms of actual speed.

[Jim K]

f00kie-

you're reply makes no sense to me... both Netgear router and the Intel 4965 operate in both 5.8Ghz & 2.4Ghz bands... maybe there's something you left out of your response...

link speeds mean absolutely nothing??? while i agree that link speeds are not real-world speeds, they i they do indicate relative real-world capability...

[DAH]

Actually I believe if you look here, you'll see that the WNR854T is a IEEE802.11n draft specification, IEEE 802.11g, IEEE 802.11b, 2.4 GHz device So your Netgear router does not do 5.8 Ghz, the Intel 4965 complies with the 2.0 standard, if it detects another device operating in the 2.4 Ghz band it will not switch into wide mode. So if you live in the city and have neighbors with an 802.11b/g access point you can not connect in wide 40 Mhz mode.

[Jim K]

DAH,

thank you for your reply, unfortunately web pages are often not updated to reflect the current status of the product... perhaps I should have mentioned that I am running the router with the latest firmware, ver. 1.4.23... take a look here and tell me what you think then:

Wi-Fi Certified™ 802.11n draft 2.0
http://kbserver.netgear.com/release_notes/d103132.asp

[DAH]

Ok I went and looked, and nothing on that page suggest to me that your WNR854T has a 5.8 GHz radio, and I believe it is unlikely that a firmware update would enable a hidden 5.8 GHz radio. Makers like to advertise their features, not hide them.

The draft 2.0 rules require the 2.4 GHz wide option to be disabled if the AP detects other devices operating in the 2.4 GHz band, so that you do not kill other AP. As your AP only works in the 2.4 GHz range I suspect that they are not implementing all of the new standard. The Intel card does limit it's connection in the 2.4 GHz to non wide operation when it detects another AP operating in non "n" mode in the 2.4 GHz band. My guess is your Intel card can detect another AP besides yours in the area.

[Jim K]

@ DAH:

doesn't the fact that I can connect at 300Mbps link speed with a WN511T PC card adapter indicate that both bands are in use?

as for why the Intel Pro 4965 connects at 144Mbps, after reading a review at Tom's Hardware
http://www.smallnetbuilder.com/content/view/30116/96/
it seems the CCA (Clear Channel Assessment) function doesn't... maybe Netgear is ignoring CCA completely in their products.

[DAH]

@ DAH:

doesn't the fact that I can connect at 300Mbps link speed with a WN511T PC card adapter indicate that both bands are in use?

as for why the Intel Pro 4965 connects at 144Mbps, after reading a review at Tom's Hardware
http://www.smallnetbuilder.com/content/view/30116/96/
it seems the CCA (Clear Channel Assessment) function doesn't... maybe Netgear is ignoring CCA completely in their products.

Sorry but the answer is still no, look at the spec on the RANGEMAX NEXT WIRELESS N NOTEBOOK ADAPTER it shows,
Wireless Speeds

802.11b: 1,2,5.5,11 Mbps
802.11g: 6, 9, 12, 18, 24, 36, 48, 54 Mbps
EWC/802.11n Draft: EWC/802.11n Draft: 6, 6.5, 13, 13.5, 19.5, 26, 27, 39, 40.5, 53, 54, 58.5, 65, 78, 81, 104,
108, 117, 121.5, 130, 135, 162, 216, 243, 270, 300 Mbps
Improves network performance up to 50% when used with legacy 802.11b/g wireless routers

Nowhere do you see, 802.11a what you are doing is bonding two channels in the 2.4 GHz band, now technically that is wrong because it interferes with your neighbor's ability to use his access point, and if you live in a city chances are very good that one or more of your neighbors has an access point. Because there are simply so many 802.11b and 802.11g devices out there already and bonding requires double the bandwidth they have decided that city users that want high performance will need to go to the 5.8 GHz band. That is more expensive to make, and is less used. You will not have interference from microwaves. Phones are much less likely to be using that area, as is your neighbor so not only will it be faster but more secure as well.

[Jim K]

Thanks for the insight, DAH.... things are starting to gell now. For some reason I always thought this router was ABGN... now I see that it is not.

Just clear one final thing up for me if you can... is the 5 GHz band in the 802.11n draft 2.0 spec the same as the 802.11a 5 GHz band? Or is it a subset if 802.11? Or are they different frequency bands and mutually exclusive of each other entirely??

[DAH]

Let me see if I can clear some of this up. 5.8 GHz is 5.8 GHz and I believe 5.4 GHz, now this is the same frequency range as used by some high end cordless phones, and 802.11a devices. Now a 802.11a device uses the same frequency range as a 802.11a/n device, but 802.11a device will not be able to use all the bandwidth of a 802.11a/n access point. Kind of like the same as with 802.11b and 802.11g devices. So when you see a 802.11n device you need to look at the other letters if you see 802.11g/n that means it works at 2.4 GHz, if you see 802.11a/n that means it works at 5.8 GHz, and if you see 802.11a/g/n this one is tricky. It may mean that it works at either 2.4 GHz or 5.8 GHz but not both at the same time or it may mean that it works at 2.4 GHz and 5.8 GHz simultaneously. You want the simultaneously versions. An access point that is an 802.11a/b/g/n simultaneously unit will appear as two access points and both can be configured. The Wireless-N Nfiniti™ Dual Band Gigabit Router & Access Point would be such a device. The AirPort Extreme Base Station can only work as either a 2.4 GHz or a 5.8 GHz access point, and only appears as one device.

So you still need to read the spec, and if it seems to good to be true it most likely is. I believe most routers doing "N" speeds in 2.4 GHz and 5.8 GHz are $200.00 plus routers. The routers doing either 2.4 or 5.8 GHz are in the $150 plus range. The routers that are "N" draft in only 2.4 GHz and most likely will never become real "n" routers should be less than $150 units. One can always find an odd ball router out there like the Belkin N1 Vision that falls outside this range.

[Jim K]

thank you DAH... your help has been very illuminating....

regards...

[Daniel]

Cut and pasted from Intel's 4965AGN driver download release notes.

Known Issues
Operating in 802.11n Mode
Intel recommends using security with your wireless network. The Intel(R) Wireless WiFi Link 4965AGN adapter can only achieve transfer rates greater than 54 Mbps on 802.11n connections when using AES security, or no security. You should only use no security when setting up or troubleshooting the network.

To enable AES for Personal Security, select WPA-Personal (AES-CCMP) or WPA2-Personal (AES-CCMP) in the Security Settings pulldown menu. To enable AES for Enterprise Security, select AES-CCMP in the Data Encryption pulldown menu.

[Patrick B]

Oh, hmm.. did your system come with N installed or did you install it yourself? If you installed it yourself do you have all 3 antenna's connected? In order to operate in 40mhz mode you need 3 antenna's. 1 each for 20mhz receive but 1 in 20mhz for send. MIMO

Actually, that's not true. MIMO is completely independent of channel size.

A 40 MHz channel happens over a single transceiver, both in the Tx and Rx paths.

MIMO is a completely different animal, as is spatial multiplexing (using antenna spacing to determine differences in signal, therefore allowing different bits to be coded onto different spatial RF streams).

You can use a 40 MHz channel without using MIMO or the multiple antennas.


Patrick

[crashnburn]

Interesting

[Jim K]

Yes Daniel, I have been using WPA2 / AES when doing my testing... If you read DAH's explaination, it explains what it going on clearly... the real problem lies with the Netgear router not having a 5 GHz radio and having an implement of Draft N v2.0 that doesn't fully adhere to the standard, but attains 300 Mb/s speeds with their own equipment in doing so. Too bad, I like their equipment a lot.

[Antioch]

I've never owned a Buffalo router - have been using D-Link successfully for the last few years.

I saw this (link router featured on Tom's Hardware (link) However it seems that this is one of the non-dual band routers.

I continued looking on Dlink's site and found this (link). It looks like it will do both 2.4GHz and 5.8GHz simultaneously. This looks like it will fit the bill? Granted, it's not yet released, but it should be soon.