My home internet is TelstraClear cable in Christchurch (low-end user, under 20GB a month and could easily live with less than the 15Mbps download speed) and we have a problem that I am fairly sure is caused by ISP transparent proxy mechanisms.
For some weeks now, seeming worse recently, we've noticed occasional slow page load times - but only for a certain set of websites that have some static page components hosted outside NZ. The most noticeable one for us is newspapers under stuff.co.nz. Normal page loads will be fast, but the long ones will be blank page for up to a minute. We can go days without noticing, then get several a day.
Every time I have turned on Firefox plugin Firebug and caught a Stuff slow load in the act, it has been waiting between 40 and 41 seconds for files from static2.stuff.co.nz. Now, a traceroute shows stuff.co.nz and static.stuff.co.nz are served by trademe.co.nz servers, but static2.stuff.co.nz goes offshore. Browsing other news sites to compare, I found on nz.yahoo.com intermittent instances of files from yimg.com taking just over 40 seconds to fetch. Different site, same amount of delay.
I also reproduced the problem from a script, eliminating browser configuration as the cause: fetching tiny files from static2.stuff.co.nz and l.yimg.com, found about 99% of fetches took under 1 second, most of the other 1% were between 40 and 41 seconds. During a 40s wait for a file, traffic to other sites is unaffected so I'm confident it is not a problem with my configuration or hardware. A brief comparative test on an Internet connection at my work (not through TelstraClear) has not produced any 40s wait there yet.
Has anyone else noticed anything similar? Any insight to confirm or refute my conclusion that it is caused by the TelstraClear proxy?