Ask HN: How to Evaluate ISP. Diagnosing timeouts.

Hi HN, I'm visiting my sister for the holidays. She owns her own start-up business and questions the reliability of her existing Internet connection and asked me to help evaluate. I tested the Comcast-provided Arris TC-862 modem/router by monitoring the RSSI Signal, SNR, and Tx Rate. As far as I can tell, the router works fine. The MCS index falls between 11-15. The Tx rate seems quite reliable, so I don't suspect any problems with the router. Normal transmission rates however around 240ms. However, when I ping Yahoo.com, I occasionally see connectivity issues like this: 64 bytes from 206.190.36.45: icmp_seq=96 ttl=42 time=178.174 ms ... Request timeout for icmp_seq 102 64 bytes from 206.190.36.45: icmp_seq=101 ttl=42 time=2272.216 ms Request timeout for icmp_seq 104 ... 64 bytes from 206.190.36.45: icmp_seq=102 ttl=42 time=5060.234 ms ... 64 bytes from 206.190.36.45: icmp_seq=104 ttl=42 time=9104.651 ms Request timeout for icmp_seq 114 ... 64 bytes from 206.190.36.45: icmp_seq=105 ttl=42 time=14243.274 ms 64 bytes from 206.190.36.45: icmp_seq=106 ttl=42 time=13242.296 ms ... 64 bytes from 206.190.36.45: icmp_seq=115 ttl=42 time=4356.262 ms 64 bytes from 206.190.36.45: icmp_seq=116 ttl=42 time=3384.265 ms 64 bytes from 206.190.36.45: icmp_seq=117 ttl=42 time=2385.716 ms 64 bytes from 206.190.36.45: icmp_seq=118 ttl=42 time=1398.363 ms Notice the transmission times out and then suffers long completion times. What can I do to find the source of these timeouts? I suspect it is the ISP and not the router. What information can I collect to confirm this? Thanks, Myles