Need Help With Network Instability

[AG124]

I was wondering if anyone here might know of somethign I can do to get my LAN working properly again. It was fine over the summer, although I had problems with it in the past. Basically, my internet connection gets cut off if I try to use even a moderate amount of bandwidth. I need to restart the modem and router to get it working again. but even then it only works for awhile. I have tried to get tech support from Linksys, but their staff didn't have any ideas (also, I have sent back one router and tried another one of the same model, but it had the same problems).

Harware Configuration (I will include some systems specs too, in case they are useful):

Router: Linksys BEFSR41 (v3)

Computer 1:
OS - Windows XP Pro
Processor - P4 3.0 Ghz
RAM - DDR 1.5 GB, 400 Mhz

Computer 2:
OS - Windows XP Pro
Processor - P4 3.0 Ghz
RAM - DDR 2.0 GB, 400 Mhz

(If you need more specs, I will post them)

Other Important Points:

- Before my brother and I returned to university for the fall semester, the router had suddenly started working fine and was still working the last time either of us used it. It has rarely been used during the fall though.

- During that period, he opened ports for Bitorrent, which increased download speeds but did not hurt the connection.

- No settings have been changed between now and then, except I have tried disabling the open ports. Whether or not they are open has no effect on the connection though, as far as I can tell.

- The Internet connection works fine when connected directly to the modem.

- My connection is configured to obtain an IP Adress and DNS server automatically. I thought I'd set it to use a static IP earlier.

- I have SP2.

- I am running a 100 MBps DSL connection from a local ISP.

- I scan for both spyware/adware and viruses and trojans on a regular basis, and never find anything more than a tracking cookie or two. I'm not sure about my brother's computer though, but it is relatively clean I think.

If anyone has any idea what is going on, or what I can do to fix this, I would greatly appreciate it. This is becoming maddening...

[Iceman]

If it works fine when you are directly connected to the modem then it has absolutly nothing more to do with your computer or modem it is either a bad ethernet cable or your ISP is issuing a dynamic address to your modem and the router is hanging onto the old address and not releasing it hence when you reboot both of them this solves the problem it is forcing it to let go of the old address and grab the new one.Now if what you are saying...you can be on the internet for hours or whatever and in the middle of surfing or whatever you can no longer connect and have to do the reboot process again?...This ..if you have a cable modem connection...could also be your modem is so close to the edge of the required specs of operation the modem is actually losing sync periodicly and going off an on so fast you may not even see the modem actually go off but the result is a very poor poor connection....run some ping tests with the modem direct and the router and compare....if you are losing packets with the router etc and not the modem.....

Type the following command at a dos prompt...

ping www.yahoo.com -t

with the router and without and see what ya see....you can copy results to the clipboard too to post here if you need as well....let me know what ya find....let me know if you are a cable modem,brand etc and maybe I can help ya more.

PS I do this for a living

I see above you are on DSL?...I am not totally familiar with how they run they're service but sounds like you need to ask them to speak with a "Lead Field Tech" and I'd bet money they can help you out here...

[AG124]

Didn't get a chance to respond earlier - I was visiting some of my family members for the first time in months (I was away at university before).

@ Iceman - Your advice sounds familiar - I got help before from a tech site, and it seems that it was something to so with the router not adjusting to the IP address. But I'm not really into networking, and I don't remember the details, or what I did to fix it. But this is the right track now. I am pretty sure there was a setting under my network settings which needed to be changed, but I don't remember what it was.

I tried pinging Yahoo - no problems with either the router or modem (except when my connection ceased, of course). Here is a typical line:

Reply from 209.73.186.238: bytes=32 time=53ms TTL=50

The last two variables were different most of the time.

As for my modem, is a Speed Touch Home, but I don't know the specific model number. All of the tech teams I used to speak to seemed to be satisfied with just that (although they could never figure out the problem). Also, I cannot stay connected for hours - about 15-20 minutes is the maximum. The crashes occur at any time - while updating software, when my brother runs Bitorrent, or when either one of us is just browsing online.

Thank You very much so far.

[Iceman]

I have a website of my own and a forum on it where I have posted some of the typical things I find and the solutions...many are wireless related but you may want to read through some of them.

http://www.cyberallies.com//support/nfphpbb/index.php

some other sites of use to me over the years are....

http://practicallynetworked.com/

and

http://www.speedguide.net/

let me know what you find....

for it to lose connection so often through the router and not when it is directly connected is suspicious to me....unless your isp is no longer seeing the MAC address of your network card or something which can be "Spoofed" in your router settings...in ther words to make it work when it is directly connected to the computer then entering the mac address of your network card into the router so the modem thinks it is still connected to the internal ethernet card....this should or is not normally a problem with my company anyway but may be what is happenening in some way...just something to try fooling around with...instead of rebooting let it connected drectly to you computer via an ethernet cable.....get connectivity....then bring up a dos prompt and run

ipconfig /all

to get the mac address of your ethernet card...then hook it back up to the router without rebooting the modem and entering the mac address of the ethernet card into the router....it should still think it is connected to the modem directly.

[The Avon Lady]

We have an ADSL phone line. Wether your service is via cable or phone line, have you checked with your cable or phone service to make sure that the line quality is what it should be? We've had problems in the past cause by poor line quality. The phone company came in, found the cause of the problem and everything went back to normal. No changes to our own hardware/software whatsoever.

[tycho102]

Well, that's a wired router, so that makes things a lot easier.

First off, look up the standard login information. Looks like "192.168.1.1" and something like "root:admin" or "admin:admin". Your instruction manual should have this stuff, or there should be a sticker on the thing.

Second, disconnect the internet cable.

Third, type in "192.168.1.1" in your browser and enter the login stuff. Visit all the configuration pages and write down all the entries. You could have PPoE information in there from your university, DNS entries.

Next, use the hard reset switch. You'll probably need a pencil. Sometimes routers will just get some funky "deny" policy setup for your system and they need a hard-reset to clear it out.

Then open up a web browser and type in "192.168.1.1". Use the login, password.



From there, it gets a bit hairy. The university probably has their own settings, and when you go somewhere else, you may have to revert back to an "default" config.

[AG124]

Actually, I'm no longer at my university - this is a home network. Don't worry aboyut it though - I got tired of the constant problems I had with this Lynksis piece of junk and just bought a D-Link DI-604 instead. It is working perfectly, unlike the Lynksis (which will make a good paperweight). Thank you for your help everyone.