Same problem, I did a number of checks on my own network using iperf and no lag spikes were showing / plr was max at 0.005%. This looks like an issue with blizzards network, it is not consistent though, randomly the world latency will spike to > 3seconds. I then have a challenge to connect (progress bar when selecting char off the login page gets stuck at 80%) then I will get a disconnected error.
Then the problem goes away for a bit. I have checked for fragmentation and routing issues, but not seeing anything. Not seeing any AS switch-overs. So I have a stable route.
Yeah seems like blizzard issue. I’ve contacted with my ISP and they said they don’t see any problem with blizzard servers. I opened a ticket 3rd times now and the only answer i got is ask forums like blizzard used to help with this kind of issues but now they just don’t care anymore. If your servers have problem how could any forum member help us ?