These are the results of a speed test on the broadband connection I will be using to connect with you. They are quite good! The important figure and the one that effects video conferencing the most is the upload speed (which is always a lot lower than any quoted download speed). You will actually be uploading four times the amount of data than you will be downloading in a video call.
If you would like to check the speed of your connection you can do it from the same site (it is free): www.speedtest.net