Anonymous FTP

Zen and the Art of the Internet

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 Anonymous FTP
 
FTP (File Transfer Protocol) is the primary method of transferring
files over the Internet.  On many systems, it's also the name of the
program that implements the protocol. Given proper permission, it's
possible to copy a file from a computer in South Africa to one in Los
Angeles at very fast speeds (on the order of 5--10K per second).
This normally requires either a user id on both systems or a special
configuration set up by the system administrator(s).
 
There is a good way around this restriction---the anonymous FTP
service.  It essentially will let anyone in the world have access to
a certain area of disk space in a non-threatening way.  With this,
people can make files publicly available with little hassle.  Some
systems have dedicated entire disks or even entire computers to
maintaining extensive archives of source code and information.  They
include gatekeeper.dec.com (Digital), wuarchive.wustl.edu (Washington
University in Saint Louis), and archive.cis.ohio-state.edu (The Ohio
State University).
 
The process involves the ``foreign'' user (someone not on the system
itself) creating an FTP connection and logging into the system as the
user anonymous, with an arbitrary password:
 
Name (foo.site.com:you): anonymous
Password: jm@south.america.org
 
Custom and netiquette dictate that people respond to the
Password: query with an email address so that the sites can
track the level of FTP usage, if they desire.  (Addresses for
information on email addresses).
 
The speed of the transfer depends on the speed of the underlying
link. A site that has a 9600bps SLIP connection will not get the same
throughput as a system with a 56k leased line (The Physical
Connection, for more on what kinds of connections can exist in a
network).  Also, the traffic of all other users on that link will
affect performance.  If there are thirty people all FTPing from one
site simultaneously, the load on the system (in addition to the
network connection) will degrade the overall throughput of the
transfer.