3.528 FTP: file-transfer protocol (135)
Willard McCarty (MCCARTY@vm.epas.utoronto.ca)
Sun, 1 Oct 89 20:48:47 EDT
Humanist Discussion Group, Vol. 3, No. 528. Sunday, 1 Oct 1989.
(1) Date: Sat, 30 Sep 89 21:38:30 CDT (87 lines)
From: nsabelli@ncsa.uiuc.edu (Nora Sabelli)
Subject: reply to a request for information on FTP
(2) Date: Sun, 1 Oct 89 00:38 EST (29 lines)
From: <LACUREJ@IUBACS>
Subject: ftp file transfers
(1) --------------------------------------------------------------------
Date: Sat, 30 Sep 89 21:38:30 CDT
From: nsabelli@ncsa.uiuc.edu (Nora Sabelli)
Subject: reply to a request for information on FTP
I hope this reply to a recent request is intelligible. If not, please
discard it...
>
> Here's a problem that has appeared on several lists but which is
> especially crucial for HUMANISTS who must use large files. Could
> someone offer a simple, step by step, and most of all intelligible
> explanation of FTP transfers? What are FTP sites? How does one access
> them? What commands must one issue? How does one find, explore, and
> analyze the directories of these knowledgte caches? In short, how is it
> done?
>
FTP (File Transfer Protocol) is one of a series of commands available
to access one computer from another, irrespective of where the
computers are located. For this to happen, the computers have to be
connected (networked) following special 'protocols' (i.e. commonly
understood ways of encoding information). The particular protocol that
can be used is called IP (Internet Protocol). TCP/IP (Transmission
Control Protocols of the IP) connections differ from Bitnet ones in
that with TCP/IP you can logon remotely to a machine, not only send
mail. In order to use FTP to transfer a file you need to have access to
accounts on both machines.
Typically, TCP/IP networks run at very fast speeds (at least faster
than Bitnet and phone lines) and this makes their use for file transfer
convenient. Groups of networks which use IP comprise the Internet;
NSFnet (the National Science Foundation network) is one if the Internet
networks; ARPAnet is another. Your campus may be connected to
Internet, or can become connected (equipment and software are needed).
If your campus is connected, and has a local area Ethernet network, you
can connect a microcomputer to the Internet provided your micro has an
ethernet card and the right software.
The two commands you need to make use of all this are TELNET (to
logon to a computer on the Internet) and FTP (to transfer files
between computers). You need to be able to identify the computer
you want to access with either an official name, or with its
o-ficial address (which is always safer). For example, the Cray
X-MP at NCSA is called ux.ncsa.uiuc.edu (the ux machine located
at NCSA which is at the University of Illinois Urbana-Champaign, an
educational institution) or 128.174.10.46 (which says exactly the
same thing, except that '46' is the machine name and '128' is the
type of institution, but where would we all be without such
inconsistencies?)
How do you find the correct machine name and address? If your
campus is connected to the Internet, the computer center should be able
to tell you; there are tables maintained by every 'node' on the
network.
Once you a) know the correct address and b) have the account number and
password for the remote computer, things become easier. The flavor of
FTP commands is Unix-like, and once you enter the FTP command itself
you have HELP. The commands you need to transfer text files are: GET,
PUT and DIR (for the remote directory of files).
Each machine's FTP program uses different words to reply, the following
example is very general:
you FTP ux.ncsa.uiuc.edu
remote machine enter account/name/
you (your account on the remote machine)
remote machine password needed
you (your password)
remote machine command:
you directory
remote machine command:
you get filename.remote filename.local
remote machine command:
you put filename.local filename.remote
remote machine command:
you help
remote machine command:
you quit
You can change directories (with the command cd), delete files, change
the file transfer mode to binary, etc. But I hope this has made clear
the process of transfering files. Many groups offer files for transfer
to everybody that wants them; in that case you don't need an account on
the remote machine. These machines are used for 'anonymous FTP' and you
use 'anonymous' for the account and your name as the password.
(2) --------------------------------------------------------------35----
Date: Sun, 1 Oct 89 00:38 EST
From: <LACUREJ@IUBACS>
Subject: ftp file transfers
> Could someone offer a simple, step by step, and most of all
> intelligible explanation of FTP transfers? What are FTP sites?
> How does one access them? What commands must one issue? ...
The problem is that there isn't such a creature. FTP
works with a variety of different computers and operating systems
and transfers all kinds of different files. The permutations
become nearly endless. The best bet is to pick a useful site
such as the military archives at SIMTEL20, and try to figure out
how to get files from there. Unless you have a local guru this
will probably require some trial and error. Also, the knowledge
gained may or may not be of help at the next site encountered.
Other possiblities are um.cc.umich.edu (35.1.1.43) or
cseg.uark.edu (130.184.64.202), both have lots of pd software for
microcomputers.
I'd be glad to send anyone a help file from SIMTEL that
can get you started in the marvelous world of tenex, hash, bget,
ebcdic, and 36-bit words with four zero filler bits.
Jon LaCure
Bitnet : lacurej@iubacs
Arpanet : lacurej@gold.bacs.indiana.edu
Voice : (812) 855-7511