WNDR3700 + cable modem problems

Hey guys,

TLDR:
I have lots of problems trying to setup Netgear WNDR3700v2 in my place. The main problem every time is that Skype connects but connections for anything else (web browsing, chat, video streaming,...) get lots of lag spikes, but work fast when there is no lag. This lag is both on 2.4GHz and 5 GHz WiFi and on all wired connections. I *think* the LAN itself works fine on WNDR3700, so the problems are internet connection related.

LONG:

Setup.

I have 10Mbit/1Mbit Time Warner Road Runner Cable (NY state area) and use Motorola SBG900 modem/wifi router to connect. The only setup that works properly -no lag issues- is connecting computers directly through that modem or through it's WiFi [the wifi is a bit slow for local network traffic, hence the WNDR3700]. The modem obtains IP address through DHCP and I can either run it with NAT with each computer getting IP 192.168.0.X or without NAT/WiFi - I assumed this disables its routing mode - it all works fine and fast.

Next, I try to network my 3 computers (2 laptops+1 desktop) using WNDR3700:
-- Attempt 1. Disabled NAT+WiFi on cable modem, then used WNDR's DHCP to setup a local network. This sort of works: the connection is established but there are major lag spike issues - see above - everything works fine for few seconds, then it starts lagging - but works fast when its not lagging.
-- Attempt 2. Enabled NAT+WiFi back on cable modem, then used WNDR as a switch. I plugged the internet connection from the modem into one of the LAN ports and it worked fine yesterday night but when I woke up nothing, except miraculously Skype, could connect.
-- Attempt 3. Left NAT+WiFi on on cable modem and setup another NAT through the WNDR3700 (yeah I know, not the most optimal), but again experienced lots of disconnections and lag spikes when trying to access anything online. Think website starts loading but never finished until you spam Refresh then it works from 3rd or 4th time you refresh the web page.

Checks.

-- 1. Replaced WNDR3700. This is my 2nd WNDR3700 (the first one was v1 tho) so it may be my network configuration thats causing issues.
-- 2. Firmware. I tried both stock firmware and OpenWRT following the WNDR3700v2 NA builds on this link: https://forum.openwrt.org/viewtopic.php?id=27722&p=1 .
-- 3. Cables. I tried using all network cables when I am directly connected to the cable modem and had no issues.
-- 4. Network adapters. Tried using WiFi card on another laptop and the wired connection on a different one and same things happen.
-- 5. Moving locations. I thought maybe there some funky interference between my cable modem and WNDR and/or desktop (they all used to be next to each other) so I moved WNDR to another part of the living room. Same problems.


I'd appreciate any feedback or suggestion of another forum where I could post this.

 

Not really helping much, but I've never expirienced any problems with my wndr3700.. is your wndr3700 connected to a modem, or are you doing something else with it?

Usually with any problems I have, I just reset the entire modem (then load the latest firmware again), then put in all my information again (password, username, setup etc..). It's a long process I know, especially if like me you have portforwarded everything, but at the end of the day, I'd rather a working router over crappy performance any day.

It's clear it's a wireless performance issue for you, so you're just gonna have to try my method, or perhaps try calling up netgear and saying 'yo.. wth!'.

Hope i helped a little.

 

That's the thing, when I disconnect it from the modem, it works fine for the local network. When it's connected to the modem, both WiFi and ethernet internet connections are laggy.

I think you have good idea, I'll pop the question on Netgear forums too and see whether I can go anywhere. I'm just too frustrated.... every time I sort of make it work I see really great improvement on WiFi (from 1-2MB/s on my old WRT54GL on WiFi b/g to 10-12MB/s on WNDR3700 n).

 

I would try using the cable modem as just a cable modem and use the good router for everything else... DHCP, firewall, routing, LAN, and WLAN.

Disable the extra features in the cable modem... WLAN, firewall, etc. Connect the cable modem Ethernet port to the WAN port on the router. Connect your wired clients to the LAN ports on the router. Enable the router features. Make sure the router's default WAN and LAN IP addresses and DHCP IP range do not conflict with the cable modem's. Configure the router's WLAN security... WPA2 + AES. And then setup your wireless clients to match.

GK

 

I read some where that Skype will route traffic through your connection if you do not limit it. I think on GRC.com had a telecast covering the issue you have.

I know that you have to setup QoS and set priority to keep the Skype from taking all of your band width. But I do not know what it is.

 

Interesting. I still have no clue how the Skype does it but one person from Netgear forums offered a suggestion and it worked!

It's basically the same what you guys are hinting at, but - apparently to get this setup going, router's mac address needs to be added to the DMZ of the modem. NOW it feels super-snappy - the same as I am directly connected to the modem. I didn't do that before and now the internet is (finally!) super-snappy!

Yay!

 

You might want to go to Home of Gibson Research Corporation and run Shields Up! to scan your system... to see if you are secured from Internet exploits.

GK

 

Good suggestion - I didn't know about this website, but I'm going through it.