I am sorry, but I have to disagree. Sometimes both your box and the server have
sufficient bandwidth, but downloads are slowed down by the interlying network.
This is because everytime a packet is sent out, it has to be routed trough
several hosts before it reaches its destination, and if those boxes have a noticeable
response time, most of the bandwidth is wasted due to waiting for the next chunk
of data. Now if you transport several chunks of data in parallel, the bandwidth
still is sufficient, but more data is transported in the same amount of time,
thus increasing "practical bandwidth". There's still a lot of waiting, but 10
times more data is sent out and received in the same amount of time.
The same goes for the "ack" packages (acknowledging that your box has received
the desired data). They have to be routed back trough the same network, and the
server won't send out the next packet unless the previous one is received. Well,
perhaps this is not entirely correct; I don't know if packets are sent out one
by one, or if there's a send queue of let's say 30 packets or so. But the
principle remains the same: the next packet is not sent out unless an acknowledgement
is received.
Of course, for modem users I still doubt that there are benefits since their
bandwidth is usually sucked up in one download anyway, but it might still improve
transfer rates to hosts which are behind a very active network.
And according to a friend here, there's still another benefit: if a server
limits download bandwidth per thread, you can get twice this bandwidth if you
download in 2 parallel threads.
On Fri, 11 Aug 2000 08:01:22 Stephen F. Bosch wrote:
> Ron Stodden wrote:
> >
> > I feel sure the original questioner was referring to the ability of
> > the Windows GetRight downloader to divide the file to be downloaded
> > into up to 10 (number is user-specified) contiguous equal chunks and
> > download them all in parallel, resulting in a single downloaded file,
> > but up to 10 times faster download.
>
> 10 times faster? Me thinks you are dreaming. Bandwidth is bandwidth, and
> there's only so much. Whether you set up 10 simultaneous downloads or do
> only one, you are going to get the file in the same period of time.
>
> Get Right just makes sure you don't waste a lot of time if your download
> craps out in the middle. It's basically a REST function for http file
> transfers =)
>
> FTP is still the way to go.
>
> Stephen
--
Lord Nightwalker aka Nighty aka DefConDos
A train stops at a train station.
A bus stops at a bus station.
On my desk I have a workstation.
