Suboptimal routes to certain ASes?

[myon98]

Hello, I use HE even though I already have native IPv6, mostly in order to experiment with a routed /48 prefix because my ISP doesn't give any. (Or can't because of the NTT NGN)

However for some destinations the latency (and throughput) were noticeably slow when going through HE compared to my native connection, and at first I thought I should use my native IPv6 when speed is important even though it would mean chopping up my precious single /64.

But when I started to look into traceroutes I realized that on certain local destinations they tend to get routed across the pacific ocean and back, gaining hundreds of milliseconds during the trip.

The most noticeable destinations were AS2500 (WIDE) and some other academic networks. Some of the hosts inside them are popular mirrors for many open source OS distributions such as {tsukuba,nara}.wide.ad.jp.

I have attached traceroute results collected today, sometimes from my HE tunnel, and because I have access to a wifi hotspot inside AS2500 I was also able to collect reverse direction as well.

Thank you for providing this service and I hope this information is helpful in some way.