US Cable Support > Time Warner Internet Services > [TWC] packet loss / service degraded - amp in rockaway park, ny

reply to kilrathi

Re: [TWC] packet loss / service degraded - amp in rockaway park,

Ahh that is sad news, but do you have any idea if plant tech or engineer would have any capibility to send a custom config file to my modem so that it only used 16qam channels for upstream and others only for qpsk initaliziation etc... Thats what I am trying to find out but its been long process. Sure they could get around and sweep the area and those frequencies and find where the problem is occuring but I dont count on that anytime soon.

I did notice something like this today on network status page:

Red 8/8/2012 7:20:00 PM HUB-E C401 4/10 30.6 MHZ

Red 8/8/2012 6:10:00 PM HUB-F C401 2/9 23.8 MHZ

under Degraded Service Outages Today!

Now I dont know whether that is related to my problem but both of those frequencies are the 64QAM frequencies used on upstream here where I live and both of them have the constant errors so I hope maybe they finally getting around to do something about this.

reply to kilrathi
I spoke with t3 tech today and he said that currently its that 30.6 MHZ channel thats constantly jumping in upstream snr between 20 and 30(this is when I have modem locked normally with all upstream channels not blocked). And since thats the channel id thats default channel so its being used for upstream and yes I have constant packet loss. This upstream snr jumping occuring on that frequency is most likely sign of some noise or interference thats causing the packet loss. I am trying again to get plant tech out there since it seems thats only the frequency thats a problem.

reply to kilrathi
So I was migrated to a new CMTS that has 6 downstream channels and all 4 upstream channels are max 16QAM last wednsday, for 5 days everything was great and I was about to call today to let them know it seems they finally after few months solved my issue when just as I double checked I noticed my connection die as I was opening some sites and so I go check my statistics and boom I see insane packet loss back:



I checked visualtrace voip tests and all that packet loss is occuring on the upstream yet again.... sigh just when I think the nightmare is finally over it strikes again, and actually right now its a lot worse than before.

The worst part of this is that most likely the noise occurs on the same frequenices on upstream channels as before but while before I was able to add splitters to have 2 of those channels T4 and then have the modem still operate on the remaining 2 for at least 24 hours without packet loss now with this new CMTS all upstream channels have QPSK modulation and thus I am unable to "drop out" certain channels anymore for an easy fix and thus if this continues I am back to square one back to same problem that started back at end of may...

reply to kilrathi
Nothing is still done, client relations rep promised me to call back last week and never did regarding update from engineering. Meanwhile anytime I see "No Ranging Response received - T3 time-out" in the log of the modem thats when packet loss jumps up on the upstream in rates of 5-20% and sometimes connection will freeze out for few minutes but the modem itself will never lose lock, I suspect it just jumps upsteam channel after that to one that has no noise but then goes back, I have pretty much narrow down which of the 4 channels have noise(packet loss) and which dont but with new cmts there is really no way to force specific one to be used as all have QPSK.

Yesterday between 3pm and 1am modem was full of T3 timeout errors and there was upstream packet loss occuring along with degraded upstream speed. Signal stats are perfect but there is noise on 1 or 2 of the upstream channels that causes the problem. There is no way to force a specific upstream channel and thus unless TW gets off their butt and manages to find out cause of the noise on the given channel I am stuck with this problem.

Since memorial day this same problem been going on and nothing is still really done about, if anything migration to new cmts only negated a way I found to solve the problem on temporary basis by myself.

Now this new cmts I been migrated to seems to be in NJ(it has NJ hostname) and I noticed that now the packet loss upstream problems kick in for past few days from about 5pm till 1-2 am so it matches more of peak time usage than packet loss problems on old cmts when it would happen all night and it was noticable even during day, now around 5pm T3 time out errors will start and the upstream is very jumpy it will be fine for 20 seconds meaning full speed and no packet loss and then bam could totally freeze for like 10 seconds or get about 20 % packet loss for a while, this all matches T3 timeout errors on the log modem, when they stop the problems stop too.

Further, there is extra cable line ran to my house from a differnt pole/tap that was left over from when they were trying to see if that will help, now I hooked up my ground block to that one and besides havign different dbmv stats there is no difference in packet loss and thus its definitely not the bad tap that I am hooked to or the line thats running in, further again coaxal from ground block to my modem is brand new no splitters etc...

I am wondering if that new cmts now is serving more customers than when I was migrated to it week ago and now its overloaded, its hard for me to say but so far past few months things are getting basically worse and even level 3 tech support and client relations are not as helpful as they were back in may. Maybe they saw that I am back paying my bill fully and think hey looks like he will just endure the problem, well last bill was last I paid now and unless I get some refund again this will be it. Still cannot get verizon fios unless its the multi dwelling vdsl so I am stuck, but this week I will be calling l3 tech every day and same with client rep I will be asking to get tech out just to drive as its a plant issue or plant tech is needed and reg tech cant do anything but hey if it takes bothering them to have to send tech all the time then I will do what I have to do over and over.

The new CMTS if in the same location as the old CMTS, not NJ.

What is your source for knowing that you are on a new CMTS?

First hop beyond my modem would be CMTS no? With old one I couldnt even resolve or ping first hop but since CMTS migration there have been 2 different 1st hops, originally a one with hostname that had nj.res in it but after I saw some scheduled work on the queens few days ago on network status page now its a ny.res first hop its kinda weird, but I assume the first hop is cmts am I correct? or at least should be near it.

Either way they had work on sunday and monday on network status page showing HUB-G C### #/# TO #/# ALL UPS FREQS under degraded service and ever since that was removed I have no problems once again for a day now, I noticed they have more ALL UPS FREQS but different hub today so maybe they been doing and are doing major work either way I am glad there are no problems again for a day but as I stated many times before there been times where everything was fine for a day or 2 and then bam, so unless I see this problem gone for like a week or 2 I wont be celebrating.

"First hop beyond my modem would be CMTS no?"

No. Modems are layer 2 devices (bridges that route packets based upon hardware addresses) and do not show up in traceroutes.

The address that you've attributed to the CMTS is actually the next router after the CMTS. Unfortunately one cannot rely too much on the location information implied by the naming of routers internal to cable systems. Keeping them up-to-date and accurate is not a priority for a lot of cable companies.

Probably has nothing to do with your problems. Sounds like they may be having some noise problems on the upstream freequencies.

Well yes, I know there is noise on upstream frequencies I know which ones too, the one positive is that new cmts uses max 16QAM on upstream and thus there is less problems in theory with noise as it can operate at lower SNR, with old cmts 2 of the channels were 64QAM and their snr would jump between 18 and 30, with old cmts i could add extra splitters that caused the 2 higher modulation channels to T4 time out due to power level being too high and then quickly remove splitter which caused only the 2 16 QAM channels/frequencies to operate for upstream, this way there was never any problems however I had to reboot the modem usually after a day since I could not renew the ip lease this way.

Based on many calls and the above results both 30.6 and 23.8Mhz frequences is where the noise occured, however T3 did mention the logs showed biggest snr jumps and noise on the 30.6Mhz frequency channel.

Currently with new cmts there been more days with no problems than with problems so I have hope. While I maybe optimistic please remember that the problem was horrible between end of may and until 2 weeks ago when cmts was migrated, and only way I had good connection was with my splitter trick. Aside from 1 month for which I got refund I still paid full 100 bucks for that service so I am more than nice to time warner. I hope that this current pattern of last 2 days holds for long as there was no T3 timeout errors or problems for nearly 2 days now.

reply to kilrathi
2 and half days things were great and overnight today T3 time out errors filled the modem log and packet loss on the upstream is back.... regular intervals 5-15% packet loss when testing voip any codec and to make matters worse client rep who promised to call me back with update last week by end of week still did not return my calls and when I call they are always busy and will call back... not sure what to think of that but I am done paying until I hear from someone.

UPDATE, packet loss on the upstream comes and goes but as before established when speaking with l3 tech this is most likely because cmts is jumping channels on the upstream and some of them have no noise(i know pretty much which ones) but since there is no way to control which channel to use there is no way to solve the problem unless they find noise thats affecting 2 of the 4 channels. However, today I also noticed there is packet loss on downstream as well, its not major but until today I never really seen any packet loss on the downstream, so either there is congestion on this cmts right now or something else is going on. Frankly back between like 2003 and 2011 I rarely seen any problems with my connection and maybe had a problem once a year that was quickly cleared up but ever since this year its pretty much problems all the time..... what does contribute to this? maybe tw pushing too many upgrades without their infastrucuture being ready for all of it not sure but its pretty pathetic.

reply to kilrathi

WOW, i'm so sorry you are still having to go through so much pain.

Have you tried calling TWC Office of the President to see what they can do to help you out?

»consumerist.com/2008/11/reach-ti···e-2.html

I also am having the same problems as you from my post:
»[11217]It all started when I upgraded to double my speeds.

I had RR since 2001 and too only had minor problems then at the end of August I upgraded my speed to max 20/1 and that is when the problems started with intermediate connection. The modem would show I am connected but I could not ping crap then it would work again. I swapped the Ubee modem for a DCM425. I had the tech guy run a new cable line through and it was fine for a couple of weeks. Then Friday my internet was out for about four hours and since then during the evening hours my connection slows to a craw with T3 timeout errors. I even downgraded back to the standard service to 10/1 but it did not make a difference. Yesterday I swapped my DCM425 for a Motorola Surfboard SBG6580 and my connection was great. I thought problem solved. I ate supper. Went online around 6 PM and my upload was slow. Then as the hours progressed the download got slow. Then at exactly 9:48 PM the T3 error logs stopped and everything was fast again.

Like you these losers at TWC have a monopoly in my block. It is either them or VDSL with no FiOS in sight every coming to my area because of underground wiring. I am at my wits end. I been calling them up everyday complaining and losing my patience. Also having to wait three weeks for a appointment is pathetic.

Im in NYC/QUEENS with 30/5 wideband service. The packet loss issue happened since last Monday. Actually, this kind of problem happened every 3~4months since last summer. The longest one was more than one month.
Every time,TWC sent a Tech and swapped the modem. However, it did not help at all.
very annoying....

reply to kilrathi
I did get a partial refund for another month and I saw 3 different tw trucks the plant tech trucks(with the lift) on tuesday around here, since yesterday everything been great and not a single T3 timeout error, however until I see no problems for longer than few days I wont be declaring anything fixed as this occured before, simply put sometimes modem would use an upstream channel where noise does not occur. Hopefully this time around they actually did do something, I will report in future hopefully with good news.

reply to kilrathi


That is my packet loss and TWC think's it's fine. I think it suck's, but don't know how to get them to fix it. Was going to make a thread, but putting it here seemed better. Any help would be nice and thanks to all.

That's a lot of packet loss.
Have you tried DSLR's line quality test to see where the loss occurs?

I could not get it to work.

I did ping with command prompt and the loss happens at over 1256 bytes. That's all I have so far.

reply to kilrathi
Unfortunately even there been patches of days where it was problem free entire weekend again a lot of upstream packet loss occuring of this nature along with ton of T3 timeout errors in model log...