There is no difference between uploading OR downloading data. The better your Internet connection speed, the faster your uploading and downloading capability. Bandwidth is the transfer rate of your connection to the Internet, plays an important role in both your upload speed and download speed. T1 or fractional T1 is the fastest, usually followed by cable, DSL, dial up and finally two cans connected by a string.
Here is an easy website tool to test your Internet connection speed: