Question: How to set up the download information on a file?

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HI,
I ran into a problem when uploaded a file onto the server and then trying to share it on the web. Most of the user has no idea how long will it take them to dl the file. I want to set up a block, which tells the user how big the size of the file, and how long will it take to dl the file via 56k, cable, DSL, t1, etc.

I am not sure how to set this up, in term of matching the file and compare it with the connection download rate speed to establish an approximation on completion time. Please help!