Router or Modem?

[Timothian]

I have had a lot of technical issues, getting them resolved, but either my router or cable modem is going bad. Not sure what one. Both are about 2 years old.

I rewired my cable lines, reduced number of splits, put in high end splitters etc. I called comcast to ask the to measure my signal strength. Comcast told my my signal strength was very strong (35.7 downloar, 32.7 upload), and I had 0 packet loss. They apparantly have statistics going back to 1 June and from their perspective, my modem has been up continuosly with no loss (not sure how they know that), with only one outage. (again, not sure how they know that, I unplug my modem all the time to reboot it). They say I am in a "green area" which means few technical issues.

About 3 months ago, my network started acting really bad and was getting IP conflict messages (not sure why this started). I changed from automaticaly assigning IP address using DCHP to using fixed IP addresses for the majority of stuff in my house. I was sure to set the ranges such that any automatic IPs would fall outside of the range of fixed IPs (in case game system was hooked up, etc..)

The status right now is that my internet connection is very solid most of the time. Download speeds of 11 mb, sometimes more. However, I still get some outages. I can go hours without a single hiccup, and sometimes they run in streaks. Outages happen regardless of what PC is up an running.

When I get an outage, there are are two different set of symptoms:

1. Cannot ping router, can't log into it, netowrk is hosed, no traffic at all on it. Wireshark running on my PC picks up no activity at my pc port (even when trying to log onto router). Not a single message.

2. I can log into my router. local network is up. But when I go to status tab in router, it does not see the cable modem, no time updates, no dns server, etc.

To fix either condition, I normally have to unplug both the modem and router. Unplugging only one of them does not seem to work. Sometimes the fix lasts a long time, other times it just keeps going down, or does not come up until a while later (which makes me think it is cable company dispite their glowing statistics).


I am tempted to think it is my router, but I do know from past experience that when the cable modem goes down, it can lock up the router.

I am confident either the router or modem needs replaced, just not sure what one.

video card - By the way, my LDs on last Thursday's raid were due to graphics locking up. Was easy to diagnose as the following day the PC stopped detecting it, and the card clearly smelled burnt. Have a new one now.

[Ralamdar]

Problem # 1.....ur using comcast... the bigest scam company ever....i had them for a total of about 2 months... the internet would drop...along with my fone?!? random... would come and go as it wanted comcast never wanted to fix shit... was a HUGE headack... my suggestion go with verizon or att if it is in ur area... comcast a pos boss...

[beornj]

From my experience and your description it sounds more like the router than the modem. Since in case 1 you are not able to access or ping the router, that tells me that is ikely the source of the problem. Another possible test case would be to ping another device when this happens. Typically the router is made up of a switch and a router port. If the router port is bad it is one thing, if it is the switch port it is a different thing. Regardless, it is the same unit and should be replaced.

I have seen where firmware upgrades can correct problems such as these. I know, sounds weird, how can it be working forever then start having problems that require firmware? I don't know, just that I have seen it happen and it is an easy and free test.

Rarely have I seen the modem go bad to cause the symptoms that you are seeing.

Hope that helps.

[Alsmack]

Router.

If you want to be 100% sure, make sure your windows firewall or some other firewall is on your PC, unplug the power from the cable modem, wire it directly to your PC, power the cable modem back up, and set your PC to get DHCP addresses.

I bet it won't drop.

To me, it sounds like you need to buy a decent router and you'll be squared away.

Also, I know all about fighting Comcast, if they say you're in a green area you might actually be okay. But they need to tell you more than just your signal strength.

If you go to http://192.168.100.1 with a web browser (assuming you have a motorola cable modem), you can see your cable modems pages. Look at your own signal strength at the modem. Make sure your power level is between -10dBmV and 10dBmV, the closer to 0 the better. The signal-to-noise ratio is usually what causes the most problems on cable networks if your power levels look fine. Unfortunately, in my case, it was the upstream SNR which was the problem, and the modem cannot measure that.

[Ylyrra]

Wow.. y'all just get all technical and I get goose bumps.

[Timothian]

Careful what you say Ylyrra, you may get some boring tells in game now.

Thanks everyone, I upgraded the firmware to the newest version, it was a bit old. None of the patch notes looked like they would affect anything, but I agree Beo, though firmware does not go bad, it could help.

Alsmack, I can't see my cable modem at that adress, well not consistently. I clicked it and clicked it, and one time the screen came up, but then I could not click on anything on it. Normally when I click that IP, I get "diagnose connection problem" So, something is preventing me from seeing it, but do not think I ever was able to, tried when I got it and never could see the modem page.

Will see what happens.

[Alsmack]

Some routers do not pass through that address, so you'll never see your cable modem web page then. You can always hook directly up to the cable modem, power cycle it, get DHCP through it and then check that web page if you wanted. I should have mentioned that it does not work with all modems/routers.

[Timothian]

Well I think my connection is better, the day after updating bios, it was the most solid it has been for a very long time. Still watching it.

Now I need help with these Orlando thunderstorms, knocked my internet out yesterday.

[Noircogi]

Does your cable modem have NAT/DHCP server in it? Most do. I'm not sure why you'd be using a router and a cable modem with NAT/DHCP. I use the NAT/DCHP in my cable modem with switches downstream of that. I also have my wireless router set up in switch mode for the same reason. That puts everything in your network on the same address space.

[Timothian]

Noir:

I do not think my modem has NAT or DCHP. I have a fairly complex set up, but all DCHP and NAT is turned off except for my router.

[Timothian]

End of story, replaced router, life is good. Network is running clean, when I put wireshark on, I get almost no bad messages, even my son is happy.


Update on my internet saga. After bios update, everything ran great, then started getting hiccups again. Tweaked the heck out of my network and wireless settings, it ran better, for a day, then bad. Replaced router and it is rock solid (for 1 week and a day)

Currently got lots of things on network, and it is stable.

[Nathanar]

Ylyrra, let's have an indepth discussion over a bottle of Kraken about defining your Routing Tables on a multi-homed server?

[Ylyrra]

Ylyrra, let's have an indepth discussion over a bottle of Kraken about defining your Routing Tables on a multi-homed server?

LOL... I'm afraid it wouldn't be very in depth as I know nothing about that. I just impresses the heck out of me that so many of y'all do.

[Nathanar]

I am nowhere near as knowledgeable as some in this guild! I just know a little about a lot lol...

[beornj]

Get a few drinks in me and I am liable to discuss with you the routing tables of 450 state offices, 3 Senate office buildings, two data centers, and the US Capitol. Not sure how many goose bumps that will give ya.