I was on the point of thinking my 50Mbit/s link was degrading badly because most of the speed test sites, inc. speedtest.net were reporting around 5MBit/s most evenings. I did manage to get it to report 50Mbit/s early one morning.
But I've just downloaded a 2.5GB ISO image from Microsoft MSDN using their standalone File Transfer Manager and that managed ~4,000KB/s which is ~45MBit/s so I was perplexed.
My guess is that either a) the speed test sites are overloaded and not to be trusted by huge factor or b) VM is doing "something" with HTTP port 80 traffic such as using a transparent proxy server. Does anyone know if VM uses HTTP proxy servers upstream? If so, then maybe one of them is going bad or is completely swamped.
But as I write, I'm questioning my logic that maybe Microsoft file transfer manager uses a different protocol or port because when one looks at the options, there are checkboxes for HTTP and HTTPs. However, you can uncheck both and it still works. Maybe it tries custom protocol/port and if that doesn't work, falls back to HTTP. That would still make sense.
Any I making any sense personally though?
---------- Post added at 21:26 ---------- Previous post was at 21:21 ----------
I've just come across www.vmspeed.com
which reports 40Mbit/s which is perfectly acceptable at this time of night.
So why is this speed test reasonably accurate and speedtest.net completely inaccurate? By a factor of 10?