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[got_milk?]

Hi everyone:

I've had my DIR-655 for a few months now and I must say, I do love it. It replaced a Linksys WRT610N which turned out to be absolute crap for me and I returned it after a week.

I have noticed though, over the past little while that when I put a load on the wireless connection the link speed falls a ton (150mbps to 54mbps sometimes) and I don't get the speed that I should have. I do have a ton of other wireless networks around, but the auto channel selection on the router keeps me far away from the other ones (they almost always use 6 and I'm up near 11 )

Using an integrated Intel WiFi Link 5100 (max 150mbps N), 1.21 Firmware (can't downgrade - I need the SharePoint software )

I changed some of the advanced network settings to try to get a better speed. They were, before I changed them:

Beacon Interval: 100ms
RTS Threshold: 2346
Fragmentation Threshold: 2346
DTIM Interval: 1
WMM Enabled
Short GI Enabled
Extra Wireless Protection Enabled

After the settings change:

Beacon Interval: 80ms
RTS Threshold: 2346
Fragmentation Threshold: 2301
DTIM Interval: 1
WMM Enabled
Short GI Enabled
Extra Wireless Protection Enabled

I only changed 2 settings, and now I have constant link speeds of 135mbps-150mbps! Great.

But, when I put a load on the router - of any sort, I started getting major lag. I started pinging the router for response times while I put loads on the router and discovered that the ping times were jumping to over 500ms, even close to 1000ms in some instances. I put the settings back, link speeds fall again and I get slow speeds but the connection has no lag.

I'm stuck at this point, any help would be appreciated. I won't be responding until tonight however as I am leaving for work.

Thanks.

[EddieZ]

I think you should restore the Fragmentation Threshold to the default setting. The small adjustment should not account for this 'improvement'. Since do probably don't know if there a many packet collissions on the network you need to know that if very few collisions (less than 5 percent) are occurring, then don't bother lowering the threshold. The additional headers applied to each fragment would dramatically increase the overhead on the network, reducing throughput. That, you want to avoid.
If significant numbers of collisions are occurring, try setting the fragmentation threshold to around 1,000 bytes first, then tweak it until you find the best results. After invoking fragmentation, follow-up with some testing to determine if the number of collisions is less and the resulting throughput is better. You should try a different setting or discontinue using it altogether if the throughput drops (even if you have fewer collisions).

Anyway, start by manually assigning a channel (1-13) and see if there is one or two that give a better connection.

[got_milk?]

Thanks for the tip, EddieZ. I turned off auto channel scan and I found channels 4 and 8-9 to be the best, now just to figure out which one is in the less populated area and I'll use that one - there are many wireless routers I can pick up around me which could be part of this issue.

I'm now getting link speeds of 135mbps-150mbps (sometimes as low as 120) and with ping times of 6ms at the max, which is very acceptable to me.

I shouldn't expect to get the full 150mbps all the time, should I? Dips as low as 120 are usually common?

Also, I noticed in the statistics page of the router, that my RX error and dropped packet counts are lower. I guess the channel I was on was a bit too overpopulated?

In any case, thanks for your help, and I'll keep tinkering a bit to find the best connection.

[onebyside]

http://www.passmark.com/products/wirelessmonitor.htm

dl and install, it's shareware

it will show you your neighbors wifi sigs and what chans they are using, pic the empty or less used.

[got_milk?]

http://www.passmark.com/products/wirelessmonitor.htm

dl and install, it's shareware

it will show you your neighbors wifi sigs and what chans they are using, pic the empty or less used.

Thanks for the utility, turns out all the APs around me use channel 11, and that's what I was trying to use...

[EddieZ]

1-6-11 are the most popular channels since those are in the middle of the spectrum and share the least with the surrounding channels.

The quality of the connection also depends on the environment, DECT phones etc do tend to influence signal quality, as do walls, ceilings and positioning of the three antennas. So it sometimes does need some trial and error to get the right setup for your specific home.

[got_milk?]

Right, so, I get a decent channel, leave the settings the way they were.

I spend most of my day playing with my new Xbox Live setup in the basement. (Link speeds 90mbps on the notebook, 360 doesn't say). 360 shows only a 1/5 bar signal strength but there's no lag and downloading's great.

I checked now at the wireless statistics and:

Received: 346268
RX Packets Dropped: 608
Errors: 124007 (roughly 35.8%)

eek! I had no problems over Live or with my notebook, I was gaming + downloading + voice chatting all at the same time without any interruptions, etc.

Obviously this isn't normal. (or is it?) The only thing I have is a DECT cordless phone which doesn't appear to be causing any harm + a 5.2GHz cordless phone downstairs. Router is on second floor, 360/laptop is in basement now.

What can I do to reduce these errors, if anything? Or am I just stuck living with them?

EDIT: I just did a little bit of searching and found this:

One probably has little or nothing to do with the other.

Every IP packet that the stack can't decode or disposition is an RX error. This includes packets and partial packets that aren't for your hardware or IP or even your WLAN (remember, these are shared frequencies).

A packet not only has to be received, it has to be received correctly. If a packet is detected but it is too short, too large, or does not pass checksum, it is counted as an error. On wireless, your wireless router is hearing a cacophony of signals -- many not even wifi, many not your wifi, many that interfere with your wifi -- all of which are sources of signals or interference that rack up the error count. Nearby signals, like those from your computers in the same home, are less ****e to error. Signals with little competing background noise, like those involving installations away from populated areas, especially 5 GHz, also are less ****e to error. Most likely, very few of the errors seen on the RX wireless side are actually from the stations on your WLAN -- most of those errors are probably partially received packets from outside your WLAN. (Your pings are still 100%.) Even if it does involve one of the stations on your WLAN, an error it doesn't mean that the page or media that you've transferred will contain an error as these travel on a higher-level protocol that assures data is received correctly before it is used or saved.

Still, if I were having this problem, my first thought would be wireless issues as well. I would first test wired and see if I got the same problem. If I did not, then ...

I would look for "automatic" wireless options to turn off while troubleshooting as switching certain modes in wireless is possible to interrupt communications: such as channel selection (choose a specific channel) and 20/40 MHz width (lock to 20). I would turn off WISH. I would probably keep the bit rate on automatic, because floating up and down appropriately is actually good for staying connected but if I suspected it, I would lock it at a relatively low speed -- such as between 11 Mbps or 24 Mbps.

If doing these things helped reliability, then I would return -- one setting at a time, then test for a while -- the changes back to defaults until I found the culprit.

Also consider settings on the station NIC (your WLAN card in your computer).

These are tough to diagnose ...

(http://www.broadbandreports.com/forum/r21620204-Help-Me-DIR655-and-High-Error-Rate)

Could this be the same sort of thing, just wireless signals that the router is receiving that aren't from any of my devices? I don't have any problems, which is making me wonder that...should I be looking for a new channel then as this one seems to be pretty crowded right now...

[funchords]

If it's working, then don't change anything. 

The message you quoted was to a person who was having errors AND symptoms of a problem, but the information on reported wireless errors is generally correct -- no way to know if it exactly fits anyone's particular situation because not all drivers report errors in the same way (or sometimes at all)

[EddieZ]

The number of errors is not really that important, unless it's almost 100% ofcourse and you have data corruption. Errors are recovered by resending the packets, so they can sometimes be noticeable, but you should not notice a couple of extra milliseconds once in while 

[got_milk?]

The number of errors is not really that important, unless it's almost 100% ofcourse and you have data corruption. Errors are recovered by resending the packets, so they can sometimes be noticeable, but you should not notice a couple of extra milliseconds once in while 

Oh, okay then. I'm not a networking guru like you guys are so I don't know how the router handles things like errors.

Well, I guess I'll leave everything the way it is then. Thanks for all of your help, everyone.

[funchords]

Glad to help.

[mchughs]

I'm geting the same choking except there doesn't seem to be a fix for it.  The same problem happens whether on my vista 64-bit laptop or my ubuntu machine hard wired into it. 

Downloading starts out great, then just chokes.  Could there be something physically wrong with my unit?

Happy New Year!!!

[EddieZ]

It would be very helpful if you gave some more information. It's obvious that P2P downloading can cause choking because of the high number of connections that are made.

But if you don't tell more about your specific problem -> don't expect a solution 

[tipstir]

Check the TTL MTU, TCP RWIN, LAN Buffer, also couple of things you can check. DRTCP, SG TCP Optimizer tools will show you what's going on. I run both N and Turbo G wireless networking. N is on it's own channel and the Turbo G is on it's own channel. I don't let the DIR-655 manage G. It only manages the N. Each Wireless Access Point 2x for Turbo G and Wireless Client Bridge also Turbo G and Wireless N Xtreme Router all have their own SSID. I just ordered another Wireless N Router to use as Wireless N Access Point where  the N signal is not showing 100% only Very Good on of 2 out 3 Wireless N laptops. The third one is showing Excellent 150mbps @ mac layer speed and physical layer speed based on chipset of 300mbps measured.