The Koodo web site says data usage is rounded up to 10K.
But they don't specify when the rounding occurs.
I'm guessing that not every TCP/IP packet gets rounded up.
But I still don't know when the rounding occurs.
Usually providers don't specify EXACTLY how they calculate data used, but I take it you are worried how fast your data will be used up... if you have other motives for your enquiry I suggest you contact Koodo Legal direct ;)
As I mentioned in the other thread 8 months ago, I am always pleasantly surprised how little data is used when I'm not in WiFi (I'm on prepaid too). I'm convinced that Koodo is fair in their calculations, sometimes rounding up but also down. I was very worried too when I signed up, because Telus rounds up at 1KB and Koodo at 10KB. I have been with both and never noticed any difference, if anything Koodo seems to use up my data slower!
I hope you'll get a definite answer, but I doubt very much you'll get it, as I said I don't think carriers are obligated to show the inside of their kitchen - they just have an obligation to serve good food :D