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File Transfer Protocol (FTP)
What is ftp? Well, first off it stands for File Transfer Protocol. It's a
protocol that allows you to transfer files between computers over a network or the
Internet. If you were to reduce it to it's most basic form, I suppose you could say it's
the no frills version of "surfing". There are no Java, graphics, music, buttons
or any other types of eye-candy.
So, why do people use it? Well, there are a good number of reasons, the first being it's
fast (due to the fact that you don't have to wait for all those bandwidth busting graphics
and applets to download.) and secondly, when you see a file listed, you can be assured
that it is actually there and not a dead link.
So how do you use this ftp thing? There are actually quite a few ways to skin this cat,
but I'll stick with the nice and easy way. There are many programs that act as a front end
interface, and their purpose is to take care of all the cryptic UNIX commands while you
just do the normal dragging and dropping that you are used to in the Explorer interface of
Windows. I was going to list a whole bunch of these "front end" programs, but it
would be easier to send you here, where you can see descriptions and such on them.
http://tucows.roppongi.or.jp/ftp95.html
My favorite (I haven't even begun to scratch the surface on trying them all yet, so this
is a biased opinion!) is CuteFTP. You can download this one at the above URL too.
As I said above, these are "front end" programs that take care of all the behind
the scenes stuff. Now, if you do ftp transfers for maintaining a web site, then you will
still have to know just a little UNIX. Maybe not the commands, but some of the knowledge
of how it functions (such as access levels for owner/group/public in reference to each of
these peoples ability to read/write/execute files and directories on the server.)
Now, you don't have to use one of these programs, because there are limited versions built
into IE4, NN4, and even Win95. Most likely you've used the ones built into IE and NN and
not even known it. Unless you're paying attention to the URL, it's pretty transparent to
you as an end user.
If you've ever seen a screen that looks kind of like a DOS "DIR"
command, then that is the FTP portion of the browser. Now, the one built into Win95, in my
experience, is pretty slow. You can use this one by opening any folder and in the address
bar, typing ftp://someplace.domain provided you have IE4 installed with the desktop
enhancements. However, your best bet is to download one of the programs from the URL I
told you about..
A vast majority of the computers available to you via http (by browser), are available for
ftp. When you log onto an ftp site, you will be asked for a login and password (from now
on, I will refer to this as l:p). So what do you put here? I'm glad you asked. There are
basically three versions of an ftp site. Closed, login list, and open.
The closed systems you don't have to worry about, because you won't be able to
access them. The login list type is one where everyone has an assigned l:p, and unless you
are one of those people, then the only way to get in these is to hack it. If any of you
are maintaining a web site, then you most likely will have an l:p for the server that
hosts your web site. The last is an open type, and it allows anonymous users. By
anonymous, the login is anonymous, and the password is generally your e-mail address. It's
not really a password, they don't have your e-mail address stored in some big database to
check it against, it's just a netiquitte (I'll be doing a newsletter on this sometime in
the future) thing.
Some server admin people like to track how many different users use their ftp
site, and because e-mail addresses are pretty unique to a single person, it is a good way
for them to do it. If you feel uncomfortable about putting your e-mail address as the
password, then make one up (Nothing bad will happen, they won't deny you access, but it's
not a nice thing to do to the admins who do like to track usage.) If you ever log onto an
ftp site, and you don't know the l:p, then just try anonymous. Most likely it will work.
Now some of you might be thinking, this must be a hackers dream right? Well, not really.
Generally, if the person setting up an ftp site has any clue at all, the security is
pretty good.
Some other things you will see during an ftp session are certain directory names. Because
a vast majority of the ftp servers out there are UNIX based, there are standard
directories that are placed in the "root" directory. Root is in quotes, because
you most likely will not really start out in the root directory (When I refer to root, I
mean the directory structure, not the user level.) ftp servers generally have a directory
set aside for ftp users to start out in. It could be /usr/ftp or usr/ftp/anonymous or
whatever. In any event, it will be transparent to you, and it will appear that you are in
the root directory.
Some of the common directories you will see are:
bin
dev
etc
incoming or uploads
outgoing or downloads
pub
You may see more or less depending on how the admin person set it up. Generally, the only
directory you will be using is the /pub directory. You can go check out the others, if you
are allowed in, you will see what is in there, if not, then it'll tell you that the
directory isn't available to you. You won't get kicked off just for trying, so see where
you can go. Now, if you are systematically trying to hack into directories, then you will
probably get kicked off, but most of you wouldn't do that right??!!? :)
So, what is stored in these directories? Well, under /pub you will most likely find
software (shareware of course, unless you're logged onto a warez (Pronounced like you were
saying "WHERE'S Leif?") site, but of course these sites are illegal (because
they contain copyrighted software which people have made available for public download.)
So, what kind of shareware? Well, let's say you are logged onto
ftp.microsoft.com They would have a majority of their Windows programs available (those
that are free or in beta.
Beta is a name given to software that has not been
publicly released yet because it is still in testing, but has been made available for
people to download so that you can in effect test it for them and provide feedback on your
experiences with the software. There is another name used called alpha, which is software
that has usually not been completed yet, but some sections do work and are made available
for people who like to crash their machines :^) You usually won't find this type of
software on any big commercial sites, but from private programmers tinkering around with
some ideas.
Sorry, huge tangent. So back to what we were talking about. There are a good
number of sites that offer nothing more than a huge repository of shareware/freeware
files. You will usually find these on .edu domain servers. A little later on in this
article, I will list some of good ftp sites for you to test your newfound knowledge on.
Some things to look for or keep in mind:
- Whether the site can resume broken downloads. This means if you get interrupted
during a download and your ftp program supports resumes, it will start back up where you
left off rather than starting all over again.
- There are two ways to transfer files. Binary and ASCII. Generally your ftp
program will automatically determine which one to use, but sometimes you may wish to set
it yourself. Binary transfers are files like .exe .com .wav, and ASCII transfers are for
text.
- Using a "front end" ftp program, you will most likely see two panes.
One pane (usually the left or top one) is for the files on your computer, while the other
pane is for the files located on the computer you are connected to.
Here are some good ftp sites to take a look at:
ftp.winsite.com
ftp.microsoft.com
oak.oakland.edu
ftp.idsoftware.com
Well, happy ftping...
