Hi Hilmar

Thanks for the info.

>>There is talk of providing 1, 2-8 Mb broadband. Some providers talk about, say, 512 Kbps.
>>
>>This made me think: just what IS 2 Mb broadband? OK the bandwidth but there's no time element in there. For instance, what DOES 2 Mb work out at as Kbps?
>>
>>Anyone?
>
>Digital bandwidth is measured in bps (bits per second - not bytes!), kbps, Mbps, etc. Unlike the usage of "kilo" for data storage (= 1024; this is standard, except amongst vendors of hard disks...), in transmission speeds, "kilo" means exactly a 1000.

Sure. It's just that everyone, used to megabytes, refers to it as "2 megabyte broadband" and I suppose it's sort of sunk in. Of course, what you say makes sense.

>
>"2 Mb" is probably just short for "2 Mbps"
>
>So, the calculations for the (theoretical) download speed of a 2 MB file are as follows:
>
>2 MB = 2 * 1024 * 1024 = 2097152 bytes = 16777216 bits.
>
>16777216 bits / 2 million bps = 8.388608 seconds; slightly over 8 seconds.

This is what I worked out, talking to Jim.

>
>All this is very theoretical; several factors can make the download slower:
>
>1) Even under ideal conditions, there is always some overhead in transmitting individual data packets (source and destination address for each packet, and some other header data, for a start). Under not-so-ideal conditions, overhead can be larger (lost packets have to be retransmitted).
>
>2) The server on the other side may be quite busy.
>
>3) TCP, in its current implementation, doesn't always take maximum advantage of available bandwidth.

Of course I was aware of traffic, etc. interfering with the max speed.

Cheers

Terry