[BoomShake007]

I have a Motorola SB5100 modem connected to a Netgear WRG614v3 router. I have 3 computers connected to that, one with a Netgear WG311, one with a D-Link ethernet card, and one with a Linksys wireless B laptop card. The three computers are also networked together via the router (file and printer sharing). I'm using Optimum Online cable service.

I've experienced some wireless network problems forever--the phone, random router shutdown, etc. Fine, I can deal with that, it only happened max once a week or if I brought the 2.4GHz phone too close. However, lately, I've experienced very frequent--several times per day--disconnects. However, my wireless signal still shows Excellent strength, 54.0Mbps. So this leads me to believe it's Mr. Modem's fault this time. All computers on the network lose connection. A powercycle (with it off for atleast a few minutes, no less) seems to fix the problem. But this is extremely annoying.

I went over to Broadbandreports.com I ran the Tweak Test, hoping maybe a setting was out of whack. It told me to use that DrTCP thing, and I followed the instructions in the FAQ. I set up the RWIN and MTU like it said. I ran the tweak test again, and now i'm getting packet loss and a 2+ second stall.
TweakTest Results
So I looked around here and saw it was suggested to use a WinsockXPfix as a possible fix to connection problems(i figured mine was considered connection problems). This didn't help. This disconnect happens after using Azureus (which I could understand perhaps overload with connections, i have max connections set to 100 and per torrent set to 60), BUT it also happens after regular browsing, which doesn't make sense to me, and even over night if I leave things on not (so no user network activity). Any help would be greatly appreciated.

Here's some info from my modem page that may be helpful:
Software Version: SB5100-2.3.1.3-SCM00-NOSH
Hardware Version: 3
MIB Version: II
GUI Version: 1.0
VxWorks Version: 5.4

Downstream Value
Frequency 603000000 Hz Locked
Signal to Noise Ratio 37 dB
Power Level 4 dB

Upstream Value
Channel ID 2
Frequency 25008000 Hz Ranged
Power Level 37 dBmV

Some Logs (first 7 on the Log page)
970-01-01 00:00:14 3-Critical 0x040D9A2C DHCP WARNING - Non-critical field invalid in response.
2005-09-01 15:17:39 3-Critical 0x04E33A10 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 timeout
2005-09-01 15:17:07 3-Critical 0x04E33A74 Started Unicast Maintenance Ranging - No Response received - T3 time-out
1970-01-01 00:00:14 3-Critical 0x040D9A2C DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:07 3-Critical 0x04E33948 No Ranging Response received - T3 time-out
1970-01-01 00:00:41 3-Critical 0x040D9A2C DHCP WARNING - Non-critical field invalid in response.
1970-01-01 00:00:38 3-Critical 0x040D9964 DHCP FAILED - Discover sent, no offer received

[Advertisements]

New TweakTest Results

Some of the problems cleared up. I'm still waiting to see if I get any disconnects.

Does anyone know of a good network monitor? As in, one that will log if and when the internet connection disconnects and/or reconnects, and perhaps what was going on at the disconnect (to check if router was bombarded with connections from something like Asureus and died)?

[BoomShake007]

New TweakTest Results

Some of the problems cleared up. I'm still waiting to see if I get any disconnects.

Does anyone know of a good network monitor? As in, one that will log if and when the internet connection disconnects and/or reconnects, and perhaps what was going on at the disconnect (to check if router was bombarded with connections from something like Asureus and died)?

[SpaceCowboy706]

Boomshake, you will probaqbly find very few people (other than me) who are able to tell you if the following levels you posted are good or bad:

This refers to the download section of your internet service: I am curious who your provider is due to the Downstream Frequency (this is not the average Docsis which normally operates at 117.03 MHz). Basically the Forward section of your signal has a Signal to Noise of 37 (AVERAGE/OK) and the Power level refers to the strength of the forward signal (+4DbMv - which is actually pretty good)

Downstream Value
Frequency 603000000 Hz Locked
Signal to Noise Ratio 37 dB
Power Level 4 dB

This refers to the reverse or upload section of your internet service: Again your frequencies are not in the norm (usually runs at 24.7Mhz). The power level refers to how hard your modem has to push to reach the first active amplifier on the mainline. There is no way to tell if this reading is good or bad unless you are willing to do some investigating and little basic math. First you need to follow your RF input line from the modem all the way back to the Ariel or Underground Mainline. You will use the following modifiers to complete an equation.

A = Tap Value = Is a little Numerical sticker on the box at the mainline (Numers to
look for are 4,11,17.20,23, 27)
B = Drop loss (1 DbMv per 100 Feet)
C = Active Loss (3.5 DbMv per 2 way splitter)(7.00 DbMv per 3 way Split)(9.00 DbMv
per 4 way split)
D = outlet Loss (1 DbMv per 100 Feet)
X = Base Modifier
Y = Maximum Transmit
Z = Minimum Transmit

Equation to calculate your Transmit level (AKA Power Level):

A + 13 + B + C + D = X
X + 3 = Y
X - 3 = Z

Your power level should fall above the Minimum Transmit of Z and below the Maximim Transmit of Y. If it is not within this Minimum and Maximum range then you have Big Problems and you need to call your Service Provider to have a Technician come find the cause. If you are in OKC and your service provider Is Cox Communications request Tech 41706 (me).

Upstream Value
Channel ID 2
Frequency 25008000 Hz Ranged
Power Level 37 dBmV

This last section refers to the modem Internal Connectivity Logs:I have numbered each log for easier reading:

The following Ebtries (T3 Timeouts refer to Noise levels within the transmitted signal) These are bad - meaning that your modem is unable to connect due to Noise Problems - I would reccomend calling your ISP, and having a service call scheduled.
Logs 3 and 5.

Some Logs (first 7 on the Log page)
(1) 970-01-01 00:00:14 3-Critical 0x040D9A2C DHCP WARNING - Non-critical field invalid in response.
(2) 2005-09-01 15:17:39 3-Critical 0x04E33A10 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 timeout
(3) 2005-09-01 15:17:07 3-Critical 0x04E33A74 Started Unicast Maintenance Ranging - No Response received - T3 time-out
(4) 1970-01-01 00:00:14 3-Critical 0x040D9A2C DHCP WARNING - Non-critical field invalid in response.
(5) 1970-01-01 00:00:07 3-Critical 0x04E33948 No Ranging Response received - T3 time-out
(6) 1970-01-01 00:00:41 3-Critical 0x040D9A2C DHCP WARNING - Non-critical field invalid in response.
(7) 1970-01-01 00:00:38 3-Critical 0x040D9964 DHCP FAILED - Discover sent, no offer received

[BoomShake007]

Wow, that's for all the info. I'll try to hunt down those variables and see whta I come up with. After that I'll give my ISP a call (Optimum Online) and tell them about the logs (and if my results are out of that range from the equation). I'll post back with my results.

Again, thanks for the in-depth reply.

[BoomShake007]

Ok, unfortunately, theres no stickers, or even numbers for that matter, on either the TV cable box (main one I assume...it says Television on it)out near the street, nor on the little cable box attached to my house. So I can't really fill in that equation :/ So should I just call Optimum Online and show them the logs and such?

EDIT: I have just emailed Cablevision/OptimumOnline about the issue, including the frequencies, power levels, etc. as well as the logs. I have indicated to them that the frequencies seem odd and the T3 time-outs are something to be concerned about. Hopefully they won't give me the cookie-cutter tech "help" run-around.

Edited by BoomShake007, 03 September 2005 - 05:45 PM.

[SpaceCowboy706]

When refering to the odd frequencies... those are set by the cable company and they dont vary.. I may not have articulated that correctly.. my fault... not normal docsis channels was all i meant...

As for emailing them about the time outs .... as a cable company employee (not mentioning any names - and dont read my profile to find out ) we are not allowed to tell the customer about issues regarding noise on the line or latency lag issues... we are supposed to give the canned answer that the problem is being looked into, the problem is with your equipment, or there is no problem at all, and lastly the problem has been corrected... which I am sure you will get one of those (reason is so we dont have to issue credits for missed services). If scheduling a service call, Just hope you get a technician that is honest and competent. Make sure to ask for a High speed internet TECH and not a Video Tech.... Broadband companies like to send Video Techs on slow speed / no sync calls, since the problem is usually cable related.

Out near the street is what your looking for.... should be a rectangle box that is metal or plastic..sticking up out of the ground... just pull the lid off and look inside...if its not a sticker then it will be stamped somewhere on it...

included a picture at this link of what your looking for; not exact replica of the ones in your system but a good comparison to see what your looking for:
http://www.tvcinc.co.....able Taps.pdf

The 27 is the tap value in this picture for "A" in the equation.

[BoomShake007]

Ok, i'll look tomorrow for a tab value.

And for a reply, I was hoping it wouldn't come to that, but in my heart I suspected it would That's usually how tech support people deal with things, in my experience using them (no offense to you...you've been amazingly helpful!)

I'll give them a call tomorrow and see what's up. Things shouldn't be this difficult

Edited by BoomShake007, 03 September 2005 - 08:37 PM.

[BoomShake007]

This is from the thread on broadbandreports.com:

The Cox guy led you astray.

Those signal frequencies are completely normal for Cablevision; in fact my modem is running at exactly those frequencies.

Also, periodic Unicast Maintenance Ranging T3 timeouts are normal. From the Cisco docs:

    quote: %UBR900-3-T3_TIMEOUT_II: R05.0 Started Unicast Maintenance Ranging no Response received. T3 time-out.

    Explanation The cable modem is online and sent a periodic Ranging Request (RNG-REQ) message to the CMTS, without receiving a Ranging Response (RNG-RSP) from the CMTS within the T3 timeout period. The cable modem will send another RNG-REQ message, up to the maximum of 16 successive attempts. This error message is DOCSIS event message is R05.0, Ranging Request.

    Recommended Action No action is needed because it is normal for a cable system to occasionally lose MAC-layer messages, especially when multiple cable modems transmit RNG-REQ messages at the same time.

I agree with GeekNJ See Profile that you need to determine whether the problem is with your router or with your connection by hooking up a computer directly to the modem.

Hmm. I seem to seriously think it's the modem. I've had router problems in the past, and when that goes, wireless signal drops to nil and I can't do a "repair connection" with the Wireless Zero Configuration thing. With most of these recent drops, signal stays excellent, I CAN do a repair and reconncect to the router, but still no internet connection. Does this indicate what I think it does, or am I thinking too logically for the computer world?

[Sopmod]

Finally! I registered just to keep an eye on this thread. I'm having daily disconnects and seeing crazy warnings and errors in my logs. Tech support was really no help. Please update this if you do get a tech called out to your house and tell us what happens. This stuff is very aggravating.

[BoomShake007]

OK, I think even without directly connecting a computer to the modem, I've narrowed down my problems to the modem.

Earlier today, the internet died again. All the tabs in Firefox I had loading timed out, I got disconnected from AIM and Gtalk, the whole shebang. However, my wireless monitor still showed excelent signal. I thought to myself "Hmmm...let's see how far I can take this." I typed in 192.168.0.1, my netgear router default IP, and that worked. Then to go further, 192.168.100.1, my default modem IP. And that worked. So I poked around that a bit, went to the Configuration page, and noticed a button saying "Restart Modem". Worth a shot, I figured, so I clicked it. I said modem would restart in 10 seconds. I waited around 20-30 seconds, then opened a new tab and tried google.com. BAM, now it's back up.

So, logically, the modem restart brought it back. Therefore, it is the modem that is causing the issues in this case. When the router goes down, I know it goes down, and signals drop (I cant get to the router page, etc. either), and usually it's explainable (stupid 2.4GHz phone too close to it, sometimes microwave, etc.). I believe it's time for a service call.

[SpaceCowboy706]

I told you they would cover up the T3 time outs.... It is noise on the line plain and simple.. wether they will admit to it or not.... read this reply from them very carefully.. i have reposted the importand part to pay aperticular attention to:::

...The cable modem is online and sent a periodic Ranging Request (RNG-REQ) message to the CMTS, without receiving a Ranging Response (RNG-RSP) from the CMTS within the T3 timeout period.....

The modem is not receiving a ranging responce because of two things....
1) Noise - BAd cable or mainline causes this, can easily be detected by performing the steps at the end of this
2) Bad modem - I have only replaced 3 bad modems in 4 1/2 years of running service calls -- all have been the cause of Noise either on the forward or reverse transmission... a favorite of Broadband techs is to say the modem is the cause, just to get the job done quickly... if you change out your modem, you will provbably run fine for a week or even a month but the same problem will return again soon, i promise you.

Determine if noise is on the line follow these ping tests.

Disable all firewalls first.. Just temporarily.. remeber to turn back on when done.
Start - run - type in "cmd" or "command" depending on your OS. When the black dos screen appears type in the following:

ping localhost -l 32 -t

This pings your network card (modem to PC)

You will start receiving replies like this:

Reply from 127.0.0.1: bytes=1000 time=<1ms ttl=128


This test will run until you press Ctrl+C to end it. Let it run for about 2 minutes and if you have "Time=" higher than <5Ms, or "Request timed out." you have either a bad modem, Cat 5 Line, or Network card.

Next Ping to do:

ping 66.210.130.10 -l 1000 -t

this is a dedicated server for just ping tests.. no other traffic goes through it. you will start receiving responce's like this:

Reply from 66.210.130.10: bytes=1000 time=15ms ttl=59

This test will run until you press Ctrl+C to end it. Let it run for about 10 minutes and if you have "Time=" higher than 80 Ms then you have NOISE. If you start getting this responce: "Request timed out." then you have serious noise problems (t3).

If both of these steps run fine then substitute the -l 1000 on the second ping test with -l 10000, run it for another ten minutes. Any Request timed outs and or "Time=" higher than 120Ms indicatres Noise Also

Hope this helps clarify the Lies from your ISP.

As an example with no noise on the line...I have normal broadband Internet service at 4Mb Downstream and 500Kb Upstream with a 3 year old modem here are my test results:

Local Host results:
Reply from 127.0.0.1: bytes=1000 time=<1ms ttl=128
ran for 5 minutes with all the same replies... good modem... good NIC.... good cat5

Ping server results at 1000Bytes
Reply from 66.210.130.10: bytes=1000 time=15ms ttl=59
Ran for 10 minutes with AVG Time 19Ms with <0% Loss>
NO NOISE

Ping server results at 10000Bytes
Reply from 66.210.130.10: bytes=10000 time=23ms ttl=68
Ran for 10 minutes with AVG Time 25Ms with <0% Loss>
NO NOISE

[Sopmod]

I'm going to run that test tonight to see what I get. Just to show what I'm dealing with:

Log

[SpaceCowboy706]

The most important part of that log is not actually the T3 time outs.. did you show this to me before? Dont think you did.

Look at the log:

SYNC Timing Synchronization Failure - Failed to acquire QAM/QPSK Symbol timing

there are 4 of them in this log ... This means that the modem has lost connectivity with the CMTS (headend). The cause of this is the Forward transmission (measured in units of QAM or Quasi Amplitude Modulation) being lost by the modem. You can tell visually when the modem does this by the blinking lights on the Modem. Based on this log your modem is a motorrolla Surfboard Model 3100 through 5120. Models 3100 through 5120 all have 4 green lights and 1 orange light if i am remebering correctly.

Lights:

First - Power
Second - Receive
Third - Send
Fourth - Online
Fifth - PC Activity


when you lose connectivity next time look at the lights on your modem and see which lights are on solid, which ones are blinking, and which ones are off.

If just light 1 is on you have power to the modem but no connectivity from the modem to the CMTS and from your PC to the modem.

If Light 1 and 2 are on and light 2 is blinking, then this means that your Modem is unable to connect to the CMTS on the Forward (AKA Downstream) transmission.

If Light1, 2, and 3 are on and Light 3 is blinking this means that your modem is able to connect to the CMTS only on the forward transmission and not on the reverse transmission (AKA Upstream).

If Lights 1, 2, 3, and 4 are on and Light 4 is blinking then this means that the modem is unable to to register with the CMTS (Usually only only happens when a modems firmware is set for Docsis 1 and the ISP is using Docsis 2... or if the modem is not provisioned correctly within the CMTS)

If, any one of these examples, the Pc activity is not blinking periodically then this means that your modem is not communicating with your PC. Common causes are bad cat5e cable, incorrect USB or NIC drivers.

Has this modem been the one you have been using since your service was started.. the reason i am asking is that the timestamps dont match up:

Example: on the very top (first) log in the time catagory the date and time is as follows: 050907145214

Year 05 / Month 09 / Day 07 / 24hour 14 / Minute 52 / Second 14
Meaning that the modem was active on September 09, 2005 at 2:52 and 14 secons PM

The logs after that correspond with the modems polling (how often the modem Syncs or No Syncs) and there are other time stamped logs that thier time stamps are incorrect...700101000018

You might ask yuou ISP about that - I dont know what is causing that, to be honest.

[Sopmod]

Thanks for your help SpaceCowboy, I really appreciate it.

The last time I noticed a disconnection, I do believe it was the 4th light (marked "online") which was blinking. Unfortnuately, I'm sleeping most of the morning now, so I won't be able to see what light blinks to confirm it. I'll check tomorrow.

When I started my service at my old place about a year ago, I was given a 4200. They gave me a 5120 when I moved. I'll try and see what my ISP says about the timestamp problems. The last time I talked about something in my logs, the guy didn't even know what I was talking about.

[SpaceCowboy706]

When you schedule out a service call with your ISP for your internet or home network messing up and they send out a technician <--- is what i do 4 days a week 12 hours a day, thats how I know about it.