rhine2 0 Newbie Poster

Hello
I am trying to develop a small program that will periodically (say every 6 hrs) calculate my ISP broadband speed (both up and dn stream) and display on my router GUI's WAN page. I am thinking of say, start a Linux timer, start down/uploading a file of a known size, stop timer and then calculate the U/D speed of the ISP.
Any good suggestions, sample program etc would be of great help. If there are open source programs out there that already does this, a link would be good.
Appreciate any/all the help!

thanks
rhine