I have a problem with my Toshiba C650D-108 Notebook.
First, my english is a little bad... sorry for this.
My Upload-Speed via Ethernet is very very slowly (20 kb/s) , but via WLAN i have 14MB per Second! The driver and windows are new and reinstalled. The Ethernet-Cable etc. are fine. The Download-Speed via Ethernet AND WLAN is perfect (16 MB per Second)
You should ask your ISP (internet service provider) for details. Mostly this depends on the terms and conditions.
In my case the download speed is much faster as upload speed.
My download speed is 13 444 kBit/s (1681kByte/s) and upload 987kBit/s (123kByte/s)
So this does not depends on LAN but on your ISP connection and rate!