I'm getting a fairly large amount of packet loss pretty regularly in the afternoons and wondering if this plot might show a reason? Any help appreciated

Thanks for writing in! I'd be more than happy to help out with this.

From what we can see in your results, this looks similar to bandwidth saturation (example: http://www.pingplotter.com/commonnetworkproblems/#bandwidthsat). Hop 1 looks like its inside your own network - probably your modem. Hop 2 is on the other side of the modem - most likely your ISP. Hop 2 and hop 19 look very similar - same latency patterns, similar packet loss. This would imply that the culprit in your issue is most likely between hop #1 and hop #2.

Your first step should probably be to do some additional testing to see if this is the case. One thing to try would be connecting your machine (the one running PingPlotter) directly to the cable modem (or router/hub) with a wire and disconnect everything else from the internet (unplug the cables and turn off wireless).

If the problem continues after disconnecting everything (keep running PingPlotter), then you've just isolated *everything else* on your network. You can then look at your machine for too much bandwidth. If you eliminate that possibility, then you've eliminated everything on your own network and you've got a case to bring to your provider.

If disconnecting everything solves the problem, then you can start isolating other devices (computers, wireless users, etc) until you've identified what's causing the problem.

We have a pretty detailed guide on how to attack this problem here:

http://www.pingplotter.com/netnirvana/

Hopefully, this gives you what you need to get started solving this problem.

Cheers!

-Phillip