Today I had installed fiber optic internet – 100Mbps download and 10Mbps upload. I was eager to test the speed. I immediately run to speedtest.net which measured download at the rang of 93Mbps but the disappointing 1Mbps upload. Then I urged to check the speed on my wife's laptop. Her upload was about 11Mbps. Then I tested the speed with on my laptop (Dell XPS 15z) over the WiFi. On the WiFi the download was 20Mbps and the upload around 11Mbps. This was a really strange situation. Then I searched on google and found this article on Dell's forum describing the exact problem which I had – http://en.community.dell.com/support-forums/laptop/f/3518/p/19427881/20015112.aspx. The problem was that I had installed a program Expact Shield which I used to watch BBC iPlayer. Expact Shield installs a VPN which somehow tunnels and slows the upload speed (probably they get a copy of what I send). After you uninstall it the problem upload problem over the Ethernet disappeared.