Download files without bandwidth bother

Many new users limit themselves to the graphically presented information on the Net. As
they gain experience at finding information, however, they grow impatient with
bandwidth-wasting and time-wasting graphics, sounds and animations. They start getting
into protocols.


This article is not about the Internet protocols referred to collectively as TCP/IP,
which are so technical that fooling around with them is like trying to modify your modem.


There's another Net protocol you should be using on a regular basis: the File Transfer
Protocol.


FTP lets you download files from Internet-connected computers without bothering with
browsers, graphics or other bandwidth hogs. It's fast, simple and efficient. It even works
for users who have only e-mail, not full Internet access.


Do you want to find out something? The best and most authoritative places to seek
answers on the Internet are in newsgroups' frequently asked questions (FAQs) lists. FTP
rapidly downloads the lists to your PC.


When you browse with Microsoft Internet Explorer or Netscape Navigator, you can sift
through indexes at various sites or search with an online engine. FTP searching is more
complicated. The most efficient way is to search all available files using an Archie
server, then ftp the files you want to your computer or server.


Unlike a Yahoo or AltaVista search on the Web that turns up useless hits, you will get
hits only on actual files you can download.


You don't need a powerful PC to use FTP. You don't even need Microsoft Windows, just an
old-style communications program.


The catchall term FTP refers both to the Unix FTP program and to commands that let you
transfer files over Internet connections. For example, if you type "get
news.txt," into a remote computer, that message would instruct the remote computer to
send you a file named news.txt.


There are other FTP commands that let you connect to remote computers, navigate
directories and establish transmission options.


FTP also has an authorized users tool that lets outsiders access the files on your
computer. That may sound like a recipe for disaster, but it isn't.


Just as only authorized LAN users can access files, only users with permission can
download files from Internet servers. People can't get to your files unless you give them
permission.


You don't have to be a member, or authorized user, of each local network to access its
files via FTP. Certain servers exist only to make files available to anyone who wants
them.


The universal user identification is "anonymous" to download public files on
FTP servers.


Although most Net servers support FTP, you won't be able to get into them unless they
have enabled the anonymous-user ID.


The way it works is simple. You must have an ID and password to access any network, but
the password need not be secret or even unique. To make your local network accessible to
anyone, just publish a single ID anyone can use to log on.


So, if you want Internet users to have access to files on your server, just specify
that "anonymous" is a valid user ID for the server, or is valid for certain
files or directories.


If you don't want to allow universal access to your files, don't make
"anonymous" a valid ID.


When an Internet server asks you for a user ID, you can always try
"anonymous." Your password for anonymous FTP servers is simply your e-mail
address or name. Some anonymous FTP sites track the password information. Other sites
don't care.


These days, we regularly hear horror stories of hacker break-ins, so the existence of a
public-access user ID that doesn't require any particular password may sound shocking at
first.


But remember that systems administrators don't make every file or directory accessible
to random visitors. Even on FTP host computers where the anonymous ID is valid, the
administrator will make only portions of the file server accessible to anonymous FTP
users.


Another security feature on anonymous FTP hosts is disabling of the FTP upload feature.


That makes it virtually impossible for malicious users to cause trouble.


Even the anonymous FTP hosts that do let you upload files will impose restrictions.
They force all uploaded files to go into one special directory reachable only by the
systems administrator.


That way, the system can check content can be checked before forwarding or posting it
in other directories.


This brings up one drawback to using FTP. The huge volume of network traffic these days
means that few managers can spare the time to check each file carefully for the latest
viruses or to see whether an uploaded file has what the author claims.


For that reason, every user who downloads files, patches or updates from an anonymous
FTP host--or anywhere else--should personally check the files for problems.


Now let's talk about FTP commands. If you work at a Unix computer, you probably already
know how FTP commands work. Enter "man ftp" at the Unix prompt to see what your
online manual has to say about FTP.


But you don't need Unix to use FTP. In fact, you don't even need full Internet access;
all you need is an e-mail account.


When you surf with a browser, it's easy to see what files are available on Web sites.
Often you can download whatever you want by clicking on a highlighted filename. Your
browser then opens up a small dialog window that lets you specify the filename and where
to store it on your computer.


In contrast, with FTP you don't automatically see what files are available.


Because there may be 1 billion or more files publicly available on various Net servers,
finding what you want to download can be a daunting task.


Here's where you turn to Archie, the Internet's card catalog.


Using another Internet protocol called Telnet, anyone can access the world's Archie
servers, all of which contain the same vast database of publicly accessible files on
anonymous FTP hosts. The Internet Archives Database goes out regularly to all Archie
servers.


Contact any Archie server via Telnet. For example, typing "telnet
archie.rutgers.edu" in Microsoft Windows' Telnet program will connect you to Rutgers
University's Archie server. Give "archie" as your user ID.


Once you see the address of the file you want, go to that site and specify the
directory and filename in the FTP command "get\dir\filename.ext" to download it.


Even though FTP and Archie commands aren't hard to understand, many Internet hosts and
networks with direct Internet connections make things even easier through helpful prompts.


For example, my local Internet provider offers a series of numbered choices for
invoking Telnet, FTP, mail, Archie and gopher services, and many other tasks from any
MS-DOS terminal program.


Here are a few basic commands to get the most out of FTP sessions.


Because FTP is Unix-based, the commands must be in lower case. You have to enter each
one after the FTP prompt.


FTP transfers files fast. But if you go through an Internet provider, you don't
actually have them on your computer yet. They're in the file section on the provider's
server, so you still have to download them or display them using vi, a Unix editor
available through any Net provider.


If you can't use FTP itself, you can send requests to an FTP mail server such as bitftp@pucc.princeton.edu.


Mail your file download requests with the commands in the body of your message, one per
line.


To learn how, send e-mail to the address above, typing in the subject line the words
"request for help." Also type the word "help" in the body of the
message.


You'll get back a set of instructions in your e-mail.


John McCormick, a free-lance writer and computer consultant, has been working with
computers since the early 1960s.


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