Visitor
•
2 Messages
Packet loss localized to first Comcast hop; outside plant repair order open since Aug 24, three truck rolls, unresolved
Intermittent video freezing since August 15. Affects Teams, Zoom, Google Meet, the Xfinity app on Apple TV, and Wi-Fi calling. Occurs on a PC, an iPad, and an Apple TV. Same devices run clean on a cellular hotspot, so the problem is the line.
Three technician visits:
Aug 19 — replaced coax from the RFoG node, swapped my modem and router for an Xfinity gateway. Symptoms returned within 24 hours.
Aug 24 — confirmed the fiber inside the condo is fine, identified the fault as being in the line outside the building, and submitted a repair order. That repair has not been performed and I have received no updates.
Aug 31 — found nothing. Speed and signal levels test in spec, which is expected since the fault is intermittent.
This morning I ran a hop-by-hop trace, 8,326 one-second samples over 2 hours 19 minutes to 8.8.8.8:
- My gateway: 0.14% loss
- Next hop, 10.28.37.186, first Comcast device beyond my gateway: 2.65% loss
- Every hop beyond that point: 2.6–2.8%, no further accumulation
Loss originates at hop 2 and is inherited unchanged downstream. Of 221 samples that failed to reach the destination, 211 failed simultaneously at hop 2. The loss comes in 48 discrete bursts, 41 of them exactly 5 seconds long, at a median interval of 2.4 minutes across the entire window. That regularity points to a physical fault rather than congestion. Note that hop 7 shows 6.10%, but hop 8 returns to 2.73%, so hop 7 is ICMP deprioritization, not the fault.
I also have a modem event log from Aug 18 showing T3 timeouts, a SYNC timing failure, and a full DOCSIS re-registration during an observed outage.
What I'm asking for: status and completion date on the Aug 24 outside plant repair order, a flap list pull for my modem at the CMTS, and a credit for degraded service since August 15. I work from home and have had to move scheduled calls to a cellular hotspot.
Raw trace data available on request.
user_hsz4rr
Visitor
•
2 Messages
9 days ago
Following up with a longer test. I extended the trace to just under six hours today, 20,809 one second samples. The results are effectively identical to the shorter run this morning, which rules out a transient event.
- My gateway: 0.11 percent packet loss
- Hop 2, 10.28.37.186, the first Comcast device beyond my gateway: 2.68 percent
- Every hop beyond that point: 2.70 percent, with no further accumulation
Three things worth noting.
Latency spikes localize to the same place as the loss. My gateway's worst sample in six hours was 197 milliseconds. Hop 2 spiked to 1,575 milliseconds, and every hop past it shows the same second-plus spikes. Loss and delay both begin at that hop.
The pattern is periodic. 133 discrete loss bursts, 100 of them exactly five seconds long, at a median interval of 2.4 minutes. That interval was also 2.4 minutes in the shorter run this morning. Something is failing on a consistent cycle.
It is not congestion. Hourly loss at hop 2 ran 4.5, 2.1, 3.5, 1.7, 2.0, 3.2 and 2.2 percent from 8 AM through 2 PM. Congestion concentrates at peak hours. This is flat across the day, which is what a physical fault looks like.
One caution for whoever reviews this: hop 7, be-33933-cs23.nota.fl.ibone.comcast.net, reads 8.00 percent, but hop 8 downstream returns to 2.70 percent. That is ICMP deprioritization at that router, not a fault. The fault is at hop 2.
This is consistent with what the August 24 technician found in the line outside the building. I can provide the raw data in CSV if it would help the maintenance team.
0
0