Niclas Hedhman wrote:
>
> Can anyone explain why it takes 1-5 minutes to get any FTP transfer to
> start, while HTTP transfers are pretty quick?
>
> Is this due to slow connections and FTP wasn't designed for high
> latency, and keep aborting and reconnecting the TCP over and over again,
> or what ??
>
> And is FTP that more efficient on the server, or why does all
> high-volume sites insist on using FTP instead of HTTP for download, such
> as Apache and Linux sites?
>
> Curious, but frustrated...
> Niclas
Slow start ups could be alot of differant things. For HTTP there is a
dedicated server sitting in memory waiting for your connections, most
FTP are run from inetd, which the ftp server isn't loaded into memory,
untill you try to make a connection to it. If the server is busy and/or
doesn't have alot of primrary memory avaiable, the ftp server will half
to fight with other processes on the server then it will have to wait
for the swap daemon to free it up some room... then it can take your
connection...
Also ftp requires a login, even if it is anonymous, http servers don't
have to use cpu cycles, bandwidth and memory to verify user name and
password... (they can if you want them to, but don't by default.).
Also depends on the machine the ftp server is running on compared to the
http server. If the company or organization thinks that their http
image is more important and spend mega bucks on beefed up http server,
they may have to use an old 486 for ftp since they blow all their money.
Also if you are tyring to "browser" and ftp by a web browser like
Netscape or IE, it will be slower, because the browser does NOT keep a
connection, it will re-login to the ftp each and everytime you switch
directories... fun fun.
Also I think HTTP is more designed for "stop and go" traffic, where as
ftp connections and expected to be connected for awhile...
Than again, I never read an entire RFC or studied anything remotely
dealing with either protrocol on a design level, so this information
could be wrong, use at your own risk..
Jack
