[thelist] PHP help wanted & fonts tip

Jay Blanchard jay.blanchard at niicommunications.com
Mon Oct 28 07:33:03 CST 2002

I am afraid to say that the example Jay just gave re connection time
calculations is not correct.

To correctly calculate download time:

1) Remember file size is in bytes, connection speed is in bits

2) 1 kilobit = 1000 bits
   1 kilobyte = 1024 bytes
   1 byte = 8 bits


>If you want to code in PHP then you can get the file size and divide it by
>known connection speeds. So if you have a file that is 86Kb;

>28Kbps connection - 3.07 seconds
>33Kbps connection - 2.61 seconds

86 kilobyte file is the same as 88,064 bytes
then multiply by 8 to get bits, which is equal to 704,512 bits

28.8 Kbps connection = 28,800 bits per second

Divide 704,512 by 28,800 you get 24 seconds.... which is not quite the same
as 3 seconds as Jay pointed out earlier...

As Jay correctly points out, this is theoretical speed.

Thanks Alex, still sleeping, math suffering.

Also, as far as I know there is no way to "get" the connection speed of a
user, so you cannot do an accurate guess of download speed for a particular
file and a particular user. You have to use the list of popular connection
speeds (14.4, 28, etc.) and do the math for the ones you desire. I would
suggest that down load times for folks with "cable and above" connections
would be unimportant unless the files you are sending are rather monsterous.


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