Troubleshooting an unstable internet connection
- by Konrad Rudolph
My MacBook Pro running OS X (10.9, but I had the same problem before) is connected to a Belkin router via WiFi and, using Virgin Media as the ISP, to the internet. The connection is extremely unstable – on some days, I get a ping timeout every few seconds. In addition, some domains seem to suffer general connectivity issues. For instance, I often find that while the youtube.com website loads, none of the videos (which are hosted on a separate domain) do. At other times, videos load but always fail to buffer, even though the actual connection speed is ok, even though I’ve disabled dash playback.
Since I’m living in a rented room and the ISP contract isn’t actually mine I’ve got only limited possibilities of addressing the problem. In particular, I have no access to the router configuration and my non tech savvy landlady, while sympathetic, is not in a great hurry to hand the problem over to the ISP’s customer support. What’s more, I seem to be the only person in the house experiencing these problems – but I can imagine that this is simply because I’m the only one who’s using the internet continuously.
I’m searching for specific tests that might be able to pinpoint – and ideally solve – the problem. So far all I’ve managed to do is establish that Virgin is routing my traffic in mysterious ways. Here’s an excerpt from traceroute google.co.uk. It’s worth mentioning that the host name doesn’t seem to matter a lot, the trace route is always the same.
traceroute: Warning: google.co.uk has multiple addresses; using 62.254.36.148
traceroute to google.co.uk (62.254.36.148), 64 hops max, 52 byte packets
1 (192.168.2.1) 1.112 ms 1.300 ms 2.359 ms
2 10.100.32.1 (10.100.32.1) 11.926 ms 10.217 ms 24.987 ms
3 cmbg-core-1a-ae3-610.network.virginmedia.net (80.1.202.93) 28.809 ms * 66.653 ms
4 popl-bb-1b-ae16-0.network.virginmedia.net (212.43.163.141) 13.759 ms 126.504 ms 20.472 ms
5 nrth-bb-1b-et-010-0.network.virginmedia.net (62.253.175.57) 28.357 ms 16.398 ms 42.387 ms
6 nrth-bb-1c-ae1-0.network.virginmedia.net (62.253.174.110) 27.441 ms 15.622 ms 12.044 ms
7 lutn-icdn-1-ae0-0.network.virginmedia.net (62.253.175.82) 16.678 ms 28.463 ms 28.253 ms
8 * * *
9 * * *
10 * * *
^C
If I let it, this goes on until the end of time. It never seems to reach a destination. Is this normal? A friend living in the same town who is also with Virgin Media has a more conventional traceroute output: 7 hops to google.co.uk, all of which send the ICMP TIME_EXCEEDED response.
The obvious fix – rebooting the router – doesn’t seem to help. As far as I can tell, the WiFi connection is stable (I can always ping the router) so the problem is further downstream.
I’ve tried using an alternative DNS before (OpenDNS) but if anything, this made things worse. In fact, it made all Google services nigh unreachable.
