US Cable Support → Time Warner Cable > Syracuse NY|TWC|Modem resets with heavy useage

Syracuse NY|TWC|Modem resets with heavy useage

Hey guys!

So Time Warner cable for the past 2 years has always been funky with me. But since I was away at school and only home for holidays and such, I just lived with the issue. But now since I'm out of school, I want to get this issue resolved, and I wanted to get input from you guys before I contacted TWC.

Ever since this started (2years ago or so) When we either have multiple users on the internet at giving time it would work good for awhile then all of a sudden the internet drops. We can still access the internet, but its slower then h***. Give it about a minute, and it will fix itself.

Starting 1 month ago, I am the only one using the internet. And the issue is:
When I am downloading a game from steam or downloading anything that is over around ~100mb The internet would cut off completly. I look at the modem and it resets itself (just like if I hit the reset button) Then after around 3minutes of it restarting, the internet is back. If the download finishes, great. The modem acts fine once again. But if it still is downloading this usually happens again. I am using a router as well, but the issue happens with or without the router, wired or wireless.

Here is info that I thought could be of use:
Modem: Touchstone™ TM402 Telephony Modem (only modem we have had since getting TWC 10+ years ago)
Router: WRT54GL (less than a year old)
Internet 15mpbs down 1mpbs up (speedtest is right on these marks)

The issue you are seeing is due to a cable modem load balancing issue. Your log shows that the modem is being "instructed" by the CMTS to change to a different upstream channel due to load, but the channel change is failing. The log states the upstream is unusable for some reason; it could be ingress noise, etc.

Thanks!
I did contact TWC and they are sending me a new modem!

You have same Arris modem for 10+years?? Thats amazing

Ya haha

I had the same problem a few years ago with an old Motorola SB4200 VoIP/eMTA modem. It worked fine for a couple years, but then one day started acting strange. Anytime I tried to upload or download anything significant, the connection would die. In my case, I often had to physically reset the modem to get back online.

a TWC tech replaced my modem with a SB5121 eMTA, which fixed the problem, as he replaced the modem he told me he had replaced a lot of the same model due to a firmware issue. TelecomENG said it best, it has something to do with the modem not being able to communicate after the CMTS requests the channel switch. It sounds completely possible that bad firmware could screw that process up. My current modem use to switch channels all the time, but as of 6-9 months ago, it seems to now stay on the same channel all the time. Not sure why, maybe enough people have moved to DOCSIS 3 modems and it's not as necessary to keep moving DOCSIS 2 modems between channels to load balance bandwidth demand.

Channel changes on DOCSIS 2 modems are somewhat annoying, since the modem can only be tuned to 1 upstream and 1 downstream channel at a time. During a channel change, you basically experience a micro-dropout, where your downstream or upstream data pauses for a moment during the channel change. Its often noticeable in a Skype conference or real time online gaming and other applications of that sort.

On DOCSIS 3 modems I would imagine the CMTS can request modems to change channels on the fly with virtually no noticeable impact or dropouts to the customer because the modem can maintain a connection to one or more channels, as other channels get dynamically reassigned.