I spent a few weeks chasing random dropouts on my home network, around 100 to 120 devices (four APs, cameras, a NAS). I was using ScreenBeam ECB7250 adapters as the coax backbone. Link speed looked fine at 3.0 to 3.6 Gbps, but stuff behind the adapters would drop off for several seconds at a time.
Here's what I found:
17 to 36 percent of my TCP connection attempts to the APs timed out, every single hour. Ping didn't show it.
The adapter's own management page reports a 128-entry bridge table, and the combined total sat at exactly 128 on every adapter I could read.
I swapped in a different brand of coax adapter on the same cable, switches and devices, and the loss dropped to about zero.
The 128 limit isn't in the datasheet or the user guide.
Screenbeam hasnt confirmed the capacity or what happens when the table fills, so I can't prove the table is the cause. The write-up covers the probe method, the packet capture, the adapter stats and Screenbeam response, and it says what is and isn't proven
Full write-up: Finding a likely 128-entry limit in MoCA adapters on a 120-device home network (debugging write-up, full technical version)
If you run one of these on a network with many IoT devices, I'd like to hear whether you see the same thing.
Here's what I found:
17 to 36 percent of my TCP connection attempts to the APs timed out, every single hour. Ping didn't show it.
The adapter's own management page reports a 128-entry bridge table, and the combined total sat at exactly 128 on every adapter I could read.
I swapped in a different brand of coax adapter on the same cable, switches and devices, and the loss dropped to about zero.
The 128 limit isn't in the datasheet or the user guide.
Screenbeam hasnt confirmed the capacity or what happens when the table fills, so I can't prove the table is the cause. The write-up covers the probe method, the packet capture, the adapter stats and Screenbeam response, and it says what is and isn't proven
Full write-up: Finding a likely 128-entry limit in MoCA adapters on a 120-device home network (debugging write-up, full technical version)
If you run one of these on a network with many IoT devices, I'd like to hear whether you see the same thing.
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