How Long Does it Take to Transfer

Whenever you have to download a large file, this becomes a persistent question, how long will it take to transfer. Last Night I wanted to download EBS 2008 Trial CD/DVD From Microsoft. It consists of 3 DVD's and 1 CD Image, Approximately a Total of about 12 GB. So the question again arises, how long will it take to transfer.

Since India is still in the age, where 256 kbps and 512 kbps is called broadband (and lucikly I have more Internet speed than you can think of), I thought of doing this article.

Assuming that there is no packet loss, i.e there is no loss of packets, by default the calculation works like this

1 Megabyte File = 1 * 8 Megabits File = 8 Megabits File
So If you had a 1 Megabits / second connection, it will take you 8 Seconds to download it.

Some Pictures to Demystify the story








Now this is not really true, you have to bear in mind, that the speed your ISP says, say 256 kbps is the speed from your home to his office, the speed to the Internet will be governed by a number of other factors.

Also the fact that when a File is transferred, using TCP/IP, the Data is bloated by 40% (L3 Headers and L2 Packet Framing).

Hence a 1 MB File becomes 1.4 MB

Assuming 256 kbps is the Internet connection speed, and you averagely only get 80% of the speed, with a 140% file size, the graphs take a different twist






So Next Time a Friend calls you to ask you to download him that big file he is unable, don't just say 10 minutes, do your math.

G