Netgear network troubles - I don't believe Netgear's answer

[rmiller1959]

I have to get the straight scoop from someone regarding my Netgear WNDR3700 router. Based on the glowing reviews and the high demand, I purchased this router last October. I saw an immediate improvement in the speed of my network, and the wireless range extended much further than any other wireless router I'd used before.

In late July, I began to experience sporadic dropouts where the router would lose its connection with the Internet. The typical error message I'd get is "DNS server not detected" or something to that effect, and the network connection icon in the system tray would have the yellow caution symbol over it. Over time, the dropouts continued, and the Internet speed slowed as well. Eventually, I contacted Netgear tech support and after a convoluted series of steps, they agreed to an RMA and they shipped me a replacement router.

Imagine my surprise when the replacement router, a refurbished unit, started behaving the same way. I swapped out cables, took my SMC gigabit switch out of the loop and connected my PC directly to the router switch, and I connected it directly to the Motorola SB6120 cable modem for several hours at a time. No matter how it connected to the router, whether direct or through another switch, and regardless of the Cat6 cable used, the dropouts and speed slowdowns continued. Here is a log I kept before Netgear told me to stop sending them information:

======================================
September 22, 2010
Restored connection to router - 12:14 PM
Dropped connection - 1:24 PM
Connection restored - 1:25 PM
Connection dropped and instantly restored - 2:44 PM
Connection dropped - 3:29 PM
Connection restored - 3:31 PM
Connection dropped and instantly restored - 3:40 PM

September 23, 2010
Connection dropped - 12:35 AM
Connection restored - 12:36 AM
Connection dropped and instantly restored - 7:54 AM
Connection dropped - 9:04 AM
Connection dropped and instantly restored - 9:41 AM
Removed connection to router - 9:59 AM

My Internet speed stayed in the 10-27 mbps range while connected to the router. Just before disconnecting from the router, my Internet speed measured about 17 mbps. Immediately after connecting directly to the modem, my Internet speed measured 51 mbps, and a re-test yielded a 56 mbps result.

Restored connection to router - 12:30 pm

Note: Initial Internet speed reading after restoring connection to router read 59 mbps. At 12:55 pm, the Internet speed slowed down to 28 mbps.
Connection dropped and instantly restored - 1:12 pm
======================================​

Supposedly, they escalated the problem to a senior engineer, and this is the response I got:

Sorry for the delay to respond you back. I would like to inform you that it is normal, it is just the LAN to WAN throughput of his router.

If you want to maximize the speed of your internet (up to 50 Mbps), then I would suggest you to change your router to a business router. Then you can try a Netgear SRXN3205 router that can handle LAN-to-WAN throughput of 60 Mbps.

Please feel free to contact us again if you will require further assistance.​

Is this a logical explanation? If so, why did the original router handle the "LAN to WAN throughput" just fine for the first nine months? And why did this router misbehave out of the box? I griped and said not only was I unwilling to accept their explanation but that, if I was forced to buy another router, it wasn't going to be a Netgear. Subsequently, I received this response:

Based on the complexity of this case, it may be appropriate for me to seek additional resources. I recommend escalating your case to the next level for further review and response. We will get back to you as soon as possible.

This message is for your information only. There is no additional action needed from you at this time. The next level support engineer will update the case and you will be notified.

Please feel free to contact us again if you will require further assistance.​

So that's where I am right now. To finish this lengthy tale, here are the components of my network:

Basement: Network rack with Motorola SB6120 cable modem, Netgear WNDR3700 router, DLink DNS-323, SMC 16-port gigabit switch, APC UPS, and a Windows Home Server PC. Two PCs and a Brother network printer connected to the network via Cat6 Ethernet. Toshiba netbook connected by Wireless-G or Wireless-N. One Sony Blu-Ray player connected via Ethernet.

First floor: One notebook PC connected by Ethernet cable when at the desktop, by Wireless-G connection when mobile. Dell network printer. DLink 8-port gigabit switch.

Second floor: One PC connected by Ethernet, two PCs connected by Wireless-N. Buffalo wireless access point to manage Wireless-N connections. One laptop connected by Wireless-G. One Xbox 360 Live connected via Wireless-G (I think - it might be Wireless-N).

Various smartphones and gadgets (Sony PSP) also use the wireless network.

My questions:

Is it the LAN to WAN throughput or are they reaching?

I'm looking at a TrendNET wired router with gigabit WAN port and 4 gigabit Ethernet ports. Will it hold up? If not, what else is there that I should consider?

Thanks!

 

[thiggins]

The "senior Engineer" is misinformed. The WNDR3700 supports over 400 Mbps of throughput, both up and downlink or simultaneously.

There are WAN (Internet connection) drops you are having, correct?

If you have the same problem when connected directly to the cable modem, the problem most likely is with your ISP. It could be that your cable modem service is oversubscribed on your node and the ISP is doing "traffic management".

Does the connection get dropped while active, idle or both?

 

[rmiller1959]

Connection drops happen regardless

Hi, Tim,

To update you on my issue:

- The connection drops were occurring regardless of whether I was active or idle. My troubleshooting involved spending several hours connected directly to the cable modem and I never experienced dropouts during those times.

- The next engineer up the chain had me adjust the router's MTU, uncheck the media server, and ensure the traffic meter was also unchecked. Initially, I lowered the MTU to 1300, which seemed to improve the connection somewhat, but didn't eliminate the dropouts entirely. I then changed it to 1492, and it seems to have eliminated the dropouts, although I'm monitoring it for a few more days to ensure that solved the problem.

- One last piece to the puzzle - perhaps. I got a message on my answering machine from Comcast about excessive bandwidth usage. I was surprised because this is the first time that's ever happened. I checked the usage statistics on Comcast and they read like this:

July: 146 GB
August: 263 GB
September: 1004 GB

The last two numbers shocked me. I've been working from home since I was laid off this past spring, but I don't think that's the cause. My daughter is taking e-learning courses, and that started last month. I tried to call the number left on the answering machine to find out what accounted for these incredible spikes in usage, but I was on hold forever, so I decided to call back later.

Could my problems be related to Comcast trying to regulate my Internet use? The dropouts were very random and and couldn't be reproduced on demand. Besides, I had no dropouts during the 2 to 4 hour blocks I was connected directly to the cable modem.

How would readjusting the MTU make a difference? I'd been using the router at its default setting of 1500 for 2/3rds of a year before my problems cropped up.

Thanks for your help!

 

[thiggins]

I've never futzed with MTU on any computer or router. Sometimes it makes a difference if you're having VPN connection problems. Otherwise I think it's a red herring. But Comcast knows their network better than I. If adjusting the MTU helped, great.

Since you didn't see the problem when connected directly to the cable modem, that tends to point back to the router. If you have another make/model router you can throw in, I'd try that.

 

[rmiller1959]

Comcast didn't recommend the MTU setting

It wasn't Comcast that recommended the MTU setting change, but rather Netgear. I thought they were stabbing in the dark, since they gave me multiple values to try. Nonetheless, it seems to have fixed the problem, so I have to give them props.

When I have the money someday, I'm going to buy a robust wired small business router and use separate wireless access points for my wireless connections. That architecture seems to work well for the wireless devices upstairs, and I've read here that it mimics enterprise LAN setups.

Thank you for taking the time to discuss this problem with me!

 

[thiggins]

Thanks for following up. Glad NETGEAR's solution worked for you. Score one for MTU futzing!