Calculating time for data transmission! (1 Viewer)

[c00kiezncreme]

Hey!
I need help...I dont get how to calculate the transmission time when u are give the file size and speed.

According to our teacher the formula is :

FILE SIZE IN BYTES/ SPEED IN BYTES PER SECOND = TIME FOR DATA TRANSMISSION

I dont get how to apply it :S

e.g the modems maximum speed is 9600bps and the photo is 4kb in size. How many seconds (approx) will it take to send?

HOw would u do that?

 

[Huy]

Originally posted by c00kiezncreme
the modems maximum speed is 9600bps and the photo is 4kb in size. How many seconds (approx) will it take to send?

HOw would u do that?

Straight from the 2003 CSSA Trial

I've answered/quoted myself a few times about this question, so I'll help

You've got a few ways of doing this.

Take the file size in kilobytes (KB), multiplying by 8 to get the total number of bits, and leaving the transmission speed in bps or bits per second.

That's easy, divide your file size (in bits) by your transmission speed (in bits) and that will give you your time of transmission (in seconds)

Using your example,

4KB = 4000 bytes (approximate)

4000 bytes * 8 = 32,000 bits
(Remember: 8 bits per byte)

Transmission speed = 9600 bps (bits per second)

Time of transmission therefore equals:

32,000 bits (4000b, 4KB)
--------------------------------
9,600 bps (bits per second)

= 3.3* seconds

So yes, your formula will work (bytes and bits, whichever you want to manipulate)

This will solely depend on what data is given, and in which units they are given in. (for example, time in minutes, needs to be converted to seconds, filesize in bits, will need to be divided by 8 to give bytes if the transmission speed is given in KB/s).

It's all about manipulation, conversion, and division (and multiplication).

 

[rx72c]

Dont mean to be rude but how many people got that wrong in the CSSA because i thought that was just a give away mark and was way too easy to get wrong.

 

[Huy]

I got it wrong, 18/20 Multiple choice so it wasn't that big a deal.

I selected 4.1 seconds? Guessed it mind you.

I know the answer was 3.41 (after the exam), using a calculator, but I had some whacked out method in the exam and went black, so I decided to go with logic/reasoning instead.

(There's another post of mine in the "2003 CSSA IPT Trial" thread, can't remember the page number im afraid)

 

[c00kiezncreme]

Thanks alot, Huy! It makes much more sense now!

 

[Huy]

Originally posted by c00kiezncreme
Thanks alot, Huy! It makes much more sense now!

Not a problem cookies, glad to help

 

[fatmuscle]

why don't you people ever use diagrams?!?!

 

[Huy]

Originally posted by fatmuscle
why don't you people ever use diagrams?!?!

Never!!!@#!$

LOL

Playing with numbers is fun though...

 

[fatmuscle]

diagrams make things so much more clearer!

btw, huy, explain:

[05:11] <Huy-> g'night all
[05:11] <Huy-> morning
[05:11] * Huy- (Huy@vw1144.bigpond.net.au) Quit (Exit: )