Wireless-N Configuration

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(Configuring your Wireless Settings for N Speeds)
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-===Configuring your Wireless Settings for N Speeds===+=General Wireless N Information=
 +First your router must be upgraded to the newest firmware (there has been talk that some older versions provide more reliable N speeds than the newest firmware, try each to figure out which fits your needs the best), and obviously MUST be an N capable unit. There are many different factors that can affect N performance. RF interference, Router brands, Congested Wireless locations etc. Also, if you have B and G clients on your network, all routers will automatically downclock to those speeds during times of shared traffic. If those devices log off, the speed should resume to N levels.
 +All N capable routers are MIMO (Multiple Input/Multiple Output). Technical [http://en.wikipedia.org/wiki/MIMO Specs] Due to this fact, multiple antennas will operate on different frequencies in order to provide the best signal quality regardless of the location.
-First your router must be upgraded to the newest firmware, and obviously MUST be an N capable unit. There are many different factors that can affect N performance. RF interference, Router brands, Congested Wireless locations etc. Also, if you have B and G clients on your network, DD-WRT will automatically downclock to those speeds.+To ensure the best operating conditions, open the Web-GUI and navigate to Status->Wireless. At the bottom there is a tab called "Site Survey." Click it to view all wireless traffic nearby and find a channel that is not being broadcasted (1-11). Use this channel you've selected if having problems with connectivity.
-All N capable routers are MIMO (Multiple Input/Multiple Output). Technical [http://en.wikipedia.org/wiki/MIMO Specs] 
-Due to this fact, multiple antennas will operate on different frequencies in order to provide the best signal quality regardless of the location. 
-To ensure the best operating conditions, open the Web-GUI and navigate to Status->Wireless. At the bottom there is a tab called "Site Survey." Click it to view all wireless traffic nearby and find a channel that is not being broadcasted (1-11). Use this channel you've selected if having problems with connectivity.+=Basic Configuration=
 +==20 MHz vs 40 Mhz==
 +Depending on the site survey in your air, you may not be able to effectively use the 40 MHz band without interference. The N spec requires for 40MHz width (2x 20MHz channels) to drop back to 1x 20MHz if it detects someone is using the additional 20MHz channel. For N with 40MHz width you should start by checking what channel in the area has the highest interference from other devices in the area, hopefully this won't be channel 6 because this part of the spectrum has to be utilized for 40MHz width in the 2.4GHz spectrum. The channel with high interference is the one you need to avoid when selecting your main channel and upper/lower 2nd channel. So if you stick to non-overlapping channels like you should, there's only 4 total possible configurations:
 +* channel 1 + 6 (channel 1 upper)
 +* channel 6 + 11 (channel 6 upper)
 +* channel 6 + 1 (channel 6 lower)
 +* channel 11 + 6 (channel 11 lower)
-As for the following, these configurations worked for that particular user. So don't think that they will work for you!+Channels are specified by their center frequency but instead of displaying (center of main 20 MHz + center of additional 20MHz) the devs opted to display it as (center of main 20MHz + center of 40MHz). Just be aware that the spectrum of channel 6 has to be used to form a 40MHz channel.
-==For the WRT310N==+Reference: [[http://www.dd-wrt.com/phpBB2/viewtopic.php?p=362989 phuzi0n troubleshoots 40 MHz problem]]
-DD-WRT v24-sp2 (09/01/09) std (SVN revision 12774M NEWD Eko)+==Wireless Security==
 +You cannot use TKIP and still get N speeds. You '''MUST''' use AES security or none at all.
-'''Basic Config''' 
 +=Problems and Resolution=
 +==Actual Speeds==
 +Even if you are connecting to your N router at 130 mbps or 270 mbps, you may get FAR lower of an actual transfer rate. This is inherent to wireless routers and cards because of overhead and interference. The best test is to play with transmit power and channels to figure out what works best for you.
-*Wireless Network Mode '''Mixed'''+In a crowded apartment complex with 20 routers, a 20 Mhz width channel was able to get about 40 mbps (5 MB/s) as an actual transfer rate.
 +==Testing==
 +When testing throughput do it ~1 meter from the AP. Doing it far away/behind walls/downstairs/etc will have reduced rates and is a different problem to solve.
 +==Device Drivers==
 +As always, make sure your wireless cards have the latest drivers. Ensure that the advanced properties of this card are set to match what your router is transmitting (examples: different channel widths, N-only)
-*Channel '''4''' (was the least populated for my area) 
-*Channel Width '''40 Mhz'''+=Device Specific Setups=
-*Wide Channel '''Upper'''+==For the WRT310N==
 +DD-WRT v24-sp2 (09/01/09) std (SVN revision 12774M NEWD Eko)
 +'''Basic Config'''
 +*Wireless Network Mode '''Mixed'''
 +*Channel '''1''' (was the least populated for my area)
 +*Channel Width '''20 Mhz'''
*Wireless Security '''WPA2 AEP''' (TKIP+AES didn't work for me) *Wireless Security '''WPA2 AEP''' (TKIP+AES didn't work for me)
- 
'''Advanced Settings''' '''Advanced Settings'''
- 
- 
*Frame Burst '''Disabled''' *Frame Burst '''Disabled'''
- 
*Afterburner '''Disabled''' *Afterburner '''Disabled'''
- 
*TX Power '''28''' *TX Power '''28'''
-==For ASUS WL500W== 
 +==For ASUS WL500W==
Using EKO SVN 13000 V24sp2 NEWD-2 Big Using EKO SVN 13000 V24sp2 NEWD-2 Big
'''Basic Config''' '''Basic Config'''
- 
*Wireless Network Mode '''Mixed''' *Wireless Network Mode '''Mixed'''
- 
*Channel '''Auto''' *Channel '''Auto'''
- 
*Channel Width '''Auto''' *Channel Width '''Auto'''
- 
*Wireless Security '''WPA2 Personal Mixed (TKIP+AES)''' *Wireless Security '''WPA2 Personal Mixed (TKIP+AES)'''
- 
'''Advanced Settings''' '''Advanced Settings'''
- 
- 
*MIMO - Transmission Fixed Rate '''Auto''' *MIMO - Transmission Fixed Rate '''Auto'''
- 
*Transmission Fixed Rate '''Auto''' *Transmission Fixed Rate '''Auto'''
- 
*Frame Burst '''Disable''' *Frame Burst '''Disable'''
- 
*Afterburner '''Disable''' *Afterburner '''Disable'''
- 
*TX Power '''71''' *TX Power '''71'''

Revision as of 03:38, 23 October 2009

Contents

General Wireless N Information

First your router must be upgraded to the newest firmware (there has been talk that some older versions provide more reliable N speeds than the newest firmware, try each to figure out which fits your needs the best), and obviously MUST be an N capable unit. There are many different factors that can affect N performance. RF interference, Router brands, Congested Wireless locations etc. Also, if you have B and G clients on your network, all routers will automatically downclock to those speeds during times of shared traffic. If those devices log off, the speed should resume to N levels.

All N capable routers are MIMO (Multiple Input/Multiple Output). Technical Specs Due to this fact, multiple antennas will operate on different frequencies in order to provide the best signal quality regardless of the location.

To ensure the best operating conditions, open the Web-GUI and navigate to Status->Wireless. At the bottom there is a tab called "Site Survey." Click it to view all wireless traffic nearby and find a channel that is not being broadcasted (1-11). Use this channel you've selected if having problems with connectivity.


Basic Configuration

20 MHz vs 40 Mhz

Depending on the site survey in your air, you may not be able to effectively use the 40 MHz band without interference. The N spec requires for 40MHz width (2x 20MHz channels) to drop back to 1x 20MHz if it detects someone is using the additional 20MHz channel. For N with 40MHz width you should start by checking what channel in the area has the highest interference from other devices in the area, hopefully this won't be channel 6 because this part of the spectrum has to be utilized for 40MHz width in the 2.4GHz spectrum. The channel with high interference is the one you need to avoid when selecting your main channel and upper/lower 2nd channel. So if you stick to non-overlapping channels like you should, there's only 4 total possible configurations:

  • channel 1 + 6 (channel 1 upper)
  • channel 6 + 11 (channel 6 upper)
  • channel 6 + 1 (channel 6 lower)
  • channel 11 + 6 (channel 11 lower)

Channels are specified by their center frequency but instead of displaying (center of main 20 MHz + center of additional 20MHz) the devs opted to display it as (center of main 20MHz + center of 40MHz). Just be aware that the spectrum of channel 6 has to be used to form a 40MHz channel.

Reference: [phuzi0n troubleshoots 40 MHz problem]

Wireless Security

You cannot use TKIP and still get N speeds. You MUST use AES security or none at all.


Problems and Resolution

Actual Speeds

Even if you are connecting to your N router at 130 mbps or 270 mbps, you may get FAR lower of an actual transfer rate. This is inherent to wireless routers and cards because of overhead and interference. The best test is to play with transmit power and channels to figure out what works best for you.

In a crowded apartment complex with 20 routers, a 20 Mhz width channel was able to get about 40 mbps (5 MB/s) as an actual transfer rate.

Testing

When testing throughput do it ~1 meter from the AP. Doing it far away/behind walls/downstairs/etc will have reduced rates and is a different problem to solve.

Device Drivers

As always, make sure your wireless cards have the latest drivers. Ensure that the advanced properties of this card are set to match what your router is transmitting (examples: different channel widths, N-only)


Device Specific Setups

For the WRT310N

DD-WRT v24-sp2 (09/01/09) std (SVN revision 12774M NEWD Eko)

Basic Config

  • Wireless Network Mode Mixed
  • Channel 1 (was the least populated for my area)
  • Channel Width 20 Mhz
  • Wireless Security WPA2 AEP (TKIP+AES didn't work for me)

Advanced Settings

  • Frame Burst Disabled
  • Afterburner Disabled
  • TX Power 28


For ASUS WL500W

Using EKO SVN 13000 V24sp2 NEWD-2 Big


Basic Config

  • Wireless Network Mode Mixed
  • Channel Auto
  • Channel Width Auto
  • Wireless Security WPA2 Personal Mixed (TKIP+AES)

Advanced Settings

  • MIMO - Transmission Fixed Rate Auto
  • Transmission Fixed Rate Auto
  • Frame Burst Disable
  • Afterburner Disable
  • TX Power 71