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D-Link FAQ => Router FAQ => FAQs => Topic started by: vrod2003 on September 11, 2008, 07:15:03 AM

Title: Lost 40mHz band
Post by: vrod2003 on September 11, 2008, 07:15:03 AM
I upgraded to 1.20, not the beta version, and setup the wireless as instructed.  Since their is no 40mHz only option, I chose Auto.  I have WPA2 only and AES cipher.  I am only getting 20mHz band as status report. 

I upgraded because I was having problems with my PC laptop running a wireless N card and I could not maintain a consistent connection via wireless.

This really needs to be fixed D-Link.  I have invested about $1,000 in your products in the last two years and resent the fact that you don't even bother to provide explanations or offer solutions to user problems.  Some of the posts in this board, the busiest of all your boards, have never been answered.  It has turned into one big gripe session.

It would be appreciated if we could get some satisfaction.  I would be willing to take an exchange to an upgraded product or a refund, but I am not willing to be ignored.  Unless D-Link wants to be in the same boat that NVIDIA is today, it would be a good idea if some real working solutions were put in place immediately.

Thank you for listening, I hope.

EXTREMELY FRUSTRATED SMALL BUSINESS OWNER
Title: Re: Lost 40mHz band
Post by: davevt31 on September 11, 2008, 08:55:52 AM
Running a 655 with the 1.20 (Not beta) also.  The "40MHz Only" is only available if your are running a N only Network Mode.  This is due to the WIFI standards.  I have N onlymode set with auto for for the channel width and always have 40 showing on the status.
Title: Re: Lost 40mHz band
Post by: bmeouf on September 11, 2008, 02:22:01 PM
The 1.20 firmware introduces a "friendly neighbor" feature (i have forgotten the exact title of this feature). Essentially it will drop your routers signal from dual 20/40mhz to 20mhz if any interference is discovered. The problem is, if you live in an area with lots of signals (even other than wifi) your wireless network connection will be degraded, and will not "compete" with other devices. This is a nice feature in concept, but most all routers do not share this 'peaceful' feature and will be overly aggressive in their broadcasting... and you will suffer as a result.

D-link made this the default approach in 1.20 firmware and it cannot be disabled. To make matters worse, from what i hear, the router will not let you downgrade to an earlier firmware once you install 1.20.

I dont know if this is the exact cause of your problem, but it sounds likely.

If anyone sees any error in my description of this feature, please let me know.

Update: I have heard people's success stories in downgrading to a firmware before 1.20 but installing a beta firmware, which will let them then install an earlier firmware. If this is something you decide you want to do you should be able to find more information about this by searching the forum.
Title: Re: Lost 40mHz band
Post by: Lycan on September 11, 2008, 04:34:13 PM
The issue with good neighbor stuff is that WiFi Alliance required us to implement it that way. we are working on a firmware that will give you the HT40 back. Maybe a mode that is not WiFi Alliance certified or some relaxed version of this new standard. As soon as the code becomes available, I'll test it and if I can post it on the forums as beta.
Title: Re: Lost 40mHz band
Post by: WildSioux on September 11, 2008, 07:43:33 PM
The issue with good neighbor stuff is that WiFi Alliance required us to implement it that way. we are working on a firmware that will give you the HT40 back. Maybe a mode that is not WiFi Alliance certified or some relaxed version of this new standard. As soon as the code becomes available, I'll test it and if I can post it on the forums as beta.


lycan, Thanks for working to get this problem fixed (hopefully).

Also, i can only hope that someone at Dlink (and other wireless companies) have let the WIFI Alliance know about the problems this "Good Neighbor policy" is causing.  As the OP has stated, we spend money on a product that is advertised to boost speeds, range, etc...and then this happens.  I blame the wifi alliance.  Seems to me that they are taking a few steps back on this.  Then again they have sat around waiting to ratify the final N standard.  Whatever, i want the 600Mbps.
Title: Re: Lost 40mHz band
Post by: Matteo on September 11, 2008, 07:52:34 PM
and they want your money.... :-*
Title: Re: Lost 40mHz band
Post by: davevt31 on September 11, 2008, 08:37:20 PM
lycan, Thanks for working to get this problem fixed (hopefully).

Also, i can only hope that someone at Dlink (and other wireless companies) have let the WIFI Alliance know about the problems this "Good Neighbor policy" is causing.  As the OP has stated, we spend money on a product that is advertised to boost speeds, range, etc...and then this happens.  I blame the wifi alliance.  Seems to me that they are taking a few steps back on this.  Then again they have sat around waiting to ratify the final N standard.  Whatever, i want the 600Mbps.
Just remember that the 'N mode" is still a draft form, final specs have not been set on it and won't be until the end of 2009.  There will probably be changes to it along the way.
Title: Re: Lost 40mHz band
Post by: WildSioux on September 12, 2008, 04:59:38 AM
Just remember that the 'N mode" is still a draft form, final specs have not been set on it and won't be until the end of 2009.  There will probably be changes to it along the way.

I realize this...Although wasnt the final standard suppose to be here by now, not later in 2009?  Changes will come, but this change is a step backwards to N standards.  Especially when the routers nearby arent doing the same.
Title: Re: Lost 40mHz band
Post by: Lycan on September 12, 2008, 08:44:10 AM
The truth of the matter is that even though N is not ratified, it can not be allowed to cause disruptions in other peoples networking hardware. For some reason the answer from them this time is to gimp newer hardware in liu of older hardware. My guess is that the WiFi alliance was concerned about newer unratified hardware causing disruptions in older legacy devices that are stable and part of mission cirtical networks like local schools and such.

This will only be a temporary setback as the world move towards faster and faster hardware. Once the Legacy B/G products have gone the way of the dodo, you'll see the 600Mbps you're looking for.
Title: Re: Lost 40mHz band
Post by: EddieZ on September 12, 2008, 10:48:31 AM

This will only be a temporary setback as the world move towards faster and faster hardware. Once the Legacy B/G products have gone the way of the dodo, you'll see the 600Mbps you're looking for.


Good luck waiting for that to happen. I guess it will take about 5 to 10 years before those 'legacy' modes are really out of the way. ::)

Title: Re: Lost 40mHz band
Post by: WildSioux on September 13, 2008, 10:28:46 AM
The truth of the matter is that even though N is not ratified, it can not be allowed to cause disruptions in other peoples networking hardware. For some reason the answer from them this time is to gimp newer hardware in liu of older hardware. My guess is that the WiFi alliance was concerned about newer unratified hardware causing disruptions in older legacy devices that are stable and part of mission cirtical networks like local schools and such.

This will only be a temporary setback as the world move towards faster and faster hardware. Once the Legacy B/G products have gone the way of the dodo, you'll see the 600Mbps you're looking for.

Good luck waiting for that to happen. I guess it will take about 5 to 10 years before those 'legacy' modes are really out of the way. ::)

Right, so in 5 to 10 years when the current G routers that people own finally die then we might be able to get N speeds.  That is if the wifi alliance ever gets around to ratifying the N standard.  Maybe that is why they keep delaying it.

"It can't not be allowed to cause disruptions in other peoples networking hardware." 
Great, so other peoples networking hardware can cause disruptions in mine... *sigh*
Title: Re: Lost 40mHz band
Post by: Tsumeone on September 14, 2008, 07:10:35 PM
The truth of the matter is that even though N is not ratified, it can not be allowed to cause disruptions in other peoples networking hardware. For some reason the answer from them this time is to gimp newer hardware in liu of older hardware. My guess is that the WiFi alliance was concerned about newer unratified hardware causing disruptions in older legacy devices that are stable and part of mission cirtical networks like local schools and such.

This will only be a temporary setback as the world move towards faster and faster hardware. Once the Legacy B/G products have gone the way of the dodo, you'll see the 600Mbps you're looking for.


Since others' (older) hardware is now disrupting my network, that's pretty backwards.  Good neighbor feature has too many flaws to speak of and it needs to go away.

There needs to be a mode in there that allows forced 40MHz and a little advisory that we (the user) accept consequences if it screws up someone's network and that it isn't wifi certified.

I should not be forced to get 1/2 of the performance I paid for because my neighbor has a free-after-rebate DI-624 that keeps rebooting itself due to it's faulty design; it is a powering-on AP and thus causes me to go down to 20MHz.
Title: Re: Lost 40mHz band
Post by: Lycan on September 15, 2008, 10:59:20 AM
Since others' (older) hardware is now disrupting my network, that's pretty backwards.  Good neighbor feature has too many flaws to speak of and it needs to go away.

There needs to be a mode in there that allows forced 40MHz and a little advisory that we (the user) accept consequences if it screws up someone's network and that it isn't wifi certified.

I should not be forced to get 1/2 of the performance I paid for because my neighbor has a free-after-rebate DI-624 that keeps rebooting itself due to it's faulty design; it is a powering-on AP and thus causes me to go down to 20MHz.
Actually we've gotten a newer firmware that relaxes the good neighbor standard and should resolve the issue.
Title: Re: Lost 40mHz band
Post by: bspvette86 on September 16, 2008, 01:08:15 PM
Can I have the "Bad neighbor" version?   ;D
Title: Re: Lost 40mHz band
Post by: EddieZ on September 16, 2008, 01:28:12 PM
I'd like to see the less unfriendly neighboor firmware too. I found out that the Neighbour function did cause degredation of the wireless connections. Since I have a lot of 54g devices around me, the 1.20 turned my signal into the dodo of the neighbourhood.
Luckily, the 1.20 B07 lets you flash back to 1.11MSbeta, making me a more aggressive neighbour. But hey, my wife and her laptop...you don't want to see her unfriendly  :o
Title: Re: Lost 40mHz band
Post by: Lycan on September 17, 2008, 01:17:12 PM
Hopefully PM will give me a copy I can post by tomorrow. I'll let you guys know.
Title: Re: Lost 40mHz band
Post by: EddieZ on September 19, 2008, 02:54:43 AM
You're the greatest
Title: Re: Lost 40mHz band
Post by: PeterF on November 12, 2008, 05:17:34 AM
It has been a while since the last post, and I wanted to know if the new firmware is in beta test.

I have a DIR-655 with a DWA-140 USB adaper, and despite trying every praticially every channel, I have been unable to get at 40mHz connection.

Netstumber doesn't report an interference on several of the channels I have tried, but still no luck.

Will the router send out a 20mHz for my "g" clients and a 40 mHz for my "n"?  or is it one or the other. 

BTW.  I am running AES and WPA2 on my "n" clients.  Thanks in advance.

Peter
Title: Re: Lost 40mHz band
Post by: Lycan on November 12, 2008, 09:26:06 AM
The WiFi alliance has made it so that anytime our router sees a 802.11b/g broadcast (client or ap) it will lower the connection speed to 20Mhz. Although tragic it is currently unavoidable. We hope to find a happy meduim in the near future.
Title: Re: Lost 40mHz band
Post by: PeterF on December 08, 2008, 04:43:10 AM
So here I was resigned to the fact that I would never go faster than 130mbs, when I rebooted my router after enabling uPnP.  Much to my amazement, the computer re-established its connection to the DIR-655 and reported 270 mbs!  A few seconds later the speed jumped to 300 mbs.   I logged back into the routed and confirmed it was using channel 7 as primary and 3 as secondary.  I've got neighbors on 1, 6, 8 and 11, so I guess I could squeeze the secondary channel in there.  After a little more playing around and configuring n-only,  WPA2 only and AES, I was able to get all the network devices in my house to see the 40 mhz channel.    Now the bad news.  The 40 mhz channel only stays active for a couple of hours.  After that I need to reboot, or change a setting and reboot to re-establish the secondary channel.  Is this the "good neighbor" kicking in after a couple of hours, or is there something I can do to improve the stability of the 40mHz band.  Thank you very much.
Title: Re: Lost 40mHz band
Post by: EddieZ on December 08, 2008, 12:32:49 PM
You could look through the WiFi alliance implementation docs to see how this feature is required to work on a router. Might also be that a neighbouring AP kicks in just a little bit more or changes channel, enabling the feature in the DIR. Any logs?
Title: Re: Lost 40mHz band
Post by: PeterF on December 08, 2008, 06:50:42 PM
OK...  Here are the rules on channel sharing from the Wi-Fi Alliance

Channel Select: A channel is deemed accessible at a node if the aggregate
interference power at the intended receiver is less than Ith (-62 dBm/MHz). The rules recognize
that a connection needs to be established between nodes before this rule can come
into operation. The channel width chosen is at the discretion of the node. A node
should be able to access any available channel in the allocation in question.

The key is that the channel width is chosen by the router based on a level of interference.  It doesn't say anything about "good neighbor" or abandoning a channel if anyone else is using it. 

Also, I checked my logs and there is not record of access point channel activity.

Maybe someone at D-Link can interpret the rule and discuss how the engineers plan to implement channel sharing.
Title: Re: Lost 40mHz band
Post by: EddieZ on December 09, 2008, 08:47:51 AM
OK...  Here are the rules on channel sharing from the Wi-Fi Alliance

Channel Select: A channel is deemed accessible at a node if the aggregate
interference power at the intended receiver is less than Ith (-62 dBm/MHz). The rules recognize
that a connection needs to be established between nodes before this rule can come
into operation. The channel width chosen is at the discretion of the node. A node
should be able to access any available channel in the allocation in question.

The key is that the channel width is chosen by the router based on a level of interference.  It doesn't say anything about "good neighbor" or abandoning a channel if anyone else is using it. 

Also, I checked my logs and there is not record of access point channel activity.

Maybe someone at D-Link can interpret the rule and discuss how the engineers plan to implement channel sharing.

Use Wireshark to see/log how strong the neighbouring signal is. This might lead you to the cause of this disappearing channel.
Title: Re: Lost 40mHz band
Post by: Lycan on December 09, 2008, 11:37:06 AM
Again, this is WiFi alliance. How they word things and what they make public is not controlled by us. As it stands this is our official PM response.

Title: Re: Lost 40mHz band
Post by: EddieZ on December 09, 2008, 11:46:27 AM
I seem to remember that the WA also has some detailled/strict tech specs published somewhere.
Dlink  just has to comply to avoid a fierce whipping.  ;D
Title: Re: Lost 40mHz band
Post by: Lycan on December 09, 2008, 11:48:53 AM
Yea, we were killing G routers. We've done it in the past with Static Turbo in the G series.
WiFi hates that.

Title: Re: Lost 40mHz band
Post by: PeterF on December 10, 2008, 04:34:17 AM
Use Wireshark to see/log how strong the neighbouring signal is. This might lead you to the cause of this disappearing channel.

OK..  I downloaded Wireshark, and is certainly a very powerful packet capture tool.  However, I don't see how it does a better job than Netstumbler of identifying my neighbor's channel and signal strength information.  Perhaps the poster could identify which test to run in order to collect the necessary data on channel interference.

Just so I am clear.  What forces a downgrade to 20mhz.  Is it a competing signal on the secondary channel, or is it a competing signal on ANY channel?  I can see about 10 neighboring access points, however the strongest is approx 30db signal less than mine.  They are also all clustered on channels 6 and 11.  None are on my primary channel (7), or occasional secondary channel (3). 

What I am looking for is an explanation of the circumstances which lead to a 20mhz downgrade (not just, "you've got neighbors").  Also how is the secondary channel determined?  In my case, it is four channels below the primary.  Ultimately, I want to understand how to improve the 40Mhz channel.  For example, move my DIR-655 to the center of the house (away from exterior windows and walls), or change the primary channel.  I can't get rid of my neighbor's access points, but I am sure there are things I can do to improve the performance of mine.  Thank you.

Title: Re: Lost 40mHz band
Post by: EddieZ on December 10, 2008, 05:03:22 AM
Wireshark is more or less the same as Netstumbler.
You can let it be active for a day or two and save the log. Pinpoint the times 40Mhz suddenly dissapears and look in the logs what the neighbouring signals looked like at that time.

You might want to email the Wifi Alliance with these questions, they made up the specs so they will be able (but willing?) to andwer you correctly. Possibly they will refer back to Dlink for the implementation, but looking at the specs there is not much Dlink can add to that.

 
Title: Re: Lost 40mHz band
Post by: Lycan on December 10, 2008, 09:11:21 AM
Any 802.11b/g beacon. Be it a client or AP side.
Title: Re: Lost 40mHz band
Post by: EddieZ on December 11, 2008, 08:33:30 AM
For example, move my DIR-655 to the center of the house (away from exterior windows and walls), or change the primary channel.  I can't get rid of my neighbor's access points, but I am sure there are things I can do to improve the performance of mine.  Thank you.

Just change the channel option to manual, pick a channel and you will see that the secondary channel will set itself in the next none overlapping channel range (1,6 and 11 are the only non overlapping channels).
So stay out of the way of neighbouring AP's. Choosing one of three channels mentioned above should give a good indication what part of the spectrum works best.

(http://www.dd-wrt.com/wiki/images/3/3e/LaFonera_Software_Chillispot_-_07_wlan_channels.gif)
Title: Re: Lost 40mHz band
Post by: funchords on December 11, 2008, 07:39:56 PM
If you can see 10 different APs from your location, you're never going to get a 40 MHz wide signal AND if you did you'd be taking a rather unfair slice.  It's the penalty for living or working in a signal-crowded environment, and you have to live with it.  If D-Link were to create an interference-causing device, the FCC rightfully would be all over them. 

This is from Atheros:


As for fixing your channel situation -- Channel 7 overlaps channel 6 by 80%.   You might as well switch to channel 6 completely, the result will be the same or perhaps a bit better.  If the bulk of your neighbors are on channel 6 or higher, then you want to be on Channel 1. 

A tip -- broadcast your SSID -- "PeterF-Channel1" which will tell your neighbors that channel 1 is already in use and encourage them to choose something else when they're figuring out their own networks.  That doesn't keep them from choosing channel 2 or 3 which will also share bandwidth with your Channel 1 network, but it might help some.