20-30% Packet Loss Every 6-8 hours.
Let me start off by saying I'm a former sub-contractor for Cox here in Las Vegas. We've had Cox internet here for around 16 months, and we didn't have to call in a single time until a little over a month ago. Since then, we had three technicians out with a fourth scheduled to come out tomorrow.
After speaking with Cox initially, we purchased a new 16x4 channel modem (replacing a 8x4 channel modem that was perfectly fine for our rated service), we also purchased a replacement router, and we replaced all ethernet wiring by hand. We did this because initially the representatives initial resolution was to reset the log files on the modem, and reboot it - not a long term fix, of course, but they wanted to blame the modem - so we did along with everything else. It goes without saying, we also run the same tests bypassing the router completely with the packet loss still being exactly the same as it was through the home hard-wired network.
We got somewhat lucky though, and our third technician found ingress feeding the tap from ALL THREE neighbors we share our 4 port tap with - one of them being bad enough to disconnect on the spot. The problem is, at the time the technician was out, we weren't experiencing the packet loss issue. So this showed us that the CMTS and tap were pretty resilient to some upstream ingress abuses.
After that, the internet was good for a solid SIX HOURS before the issue came back. 20-30% Packet Loss when running a ping straight to head-end (10.74.128.1). This happens nearly every day around 6pm to around 12pm, and on the weekends it happens in the middle of the day as well. Sometimes it happens for 3 minutes, and goes away for 3 hours, and sometimes it happens for 6 hours, and goes away for an hour.
After a month of research, and testing, and technicians, the issue is clear - ALL THREE of my neighbors who I share a tap with are feeding enough UPSTREAM INGRESS in to the tap, that our return path is being drowned out by the noise.
Some more evidence that it's an issue with UPSTREAM INGRESS from all of our neighbors is that when the issue is going strong, the SNR on 2 of the our 4 upstream channels falls below 20 (confirmed by two Cox reps).
Some further proof that it's an issue with UPSTREAM INGRESS is that my modem has no T4 timeouts, the few it has is from me disconnecting the cable from it when swapping modems. But it sure gets a lot of T3 timeouts. The reason is never gets T4 timeouts is because the modem always receives the message to send a ranging requests from the CMTS (because that would be a DOWNSTREAM action). And the T3 timeouts are caused by my modem attempting to respond to those ranging requests, but instead being drowned out by my three neighbors UPSTREAM INGRESS.
After that wall of text, here's my concluding question:
We have a fourth technician coming out tomorrow, what do I have to say or do in order to actually resolve this issue for good? Thanks.
