FTPmail
Encyclopedia
FTPmail is the term used for the practice of using an FTPmail server to gain access to various files over the Internet
. An FTPmail server is a proxy server
which (asynchronously) connects to remote FTP
servers in response to email requests, returning the downloaded files as an email attachment. This service might be useful to users who cannot themselves initiate an FTP session—for example, because they are constrained by restrictions on their Internet access.
FTPmail gateways allowed people to retrieve such files. The file was broken into smaller pieces and encoded using a popular format such as uuencode
. The receiver of the email messages would later reassemble the original file and decode it. As the file was broken into smaller pieces, the chances of losing the transmission was much smaller. In case of loss of connectivity, the transmission could be restarted from that part. The process was slower but much more reliable. It also allowed people who accessed the Internet only for email, using dial-up lines, to download files that were located remotely, and even if they weren't actually connected online to the Internet (for example, using BBSs or other specialized e-mail software).
Popular examples were the servers located at universities such as ftpmail@sunsite.unc.edu and bitftp@pucc.princeton.edu, which hosted repositories containing the earlier versions of Linux and other GNU software. Access to these repositories via FTPmail was instrumental at allowing people from foreign countries to try to adopt these tools at a time where online connectivity was impossible.
FTPmail services were common in the 1990s, but have dwindled in importance as FTP lost popularity in favour of other methods for file transfer, notably HTTP which is available to virtually all Internet users.
is sent to a FTPmail server with the command to be performed, inserted as the body of the message. The server then processes the request by logging on to the remote site and returning the result via email.
Internet
The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide...
. An FTPmail server is a proxy server
Proxy server
In computer networks, a proxy server is a server that acts as an intermediary for requests from clients seeking resources from other servers. A client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resource available from a different server...
which (asynchronously) connects to remote FTP
File Transfer Protocol
File Transfer Protocol is a standard network protocol used to transfer files from one host to another host over a TCP-based network, such as the Internet. FTP is built on a client-server architecture and utilizes separate control and data connections between the client and server...
servers in response to email requests, returning the downloaded files as an email attachment. This service might be useful to users who cannot themselves initiate an FTP session—for example, because they are constrained by restrictions on their Internet access.
History
During the early years of the Internet, Internet access was limited to a few locations. High speed links were not available for most users, and online connectivity was rare and expensive. Download of big files was nearly impossible due to the frequent errors and retransmissions, which led to the loss of the TCP/IP connection. The original FTP specification did not allow for a session to be resumed, and the transmission had to restart from the beginning.FTPmail gateways allowed people to retrieve such files. The file was broken into smaller pieces and encoded using a popular format such as uuencode
Uuencode
Uuencoding is a form of binary-to-text encoding that originated in the Unix program uuencode, for encoding binary data for transmission over the uucp mail system.The name "uuencoding" is derived from "Unix-to-Unix encoding"...
. The receiver of the email messages would later reassemble the original file and decode it. As the file was broken into smaller pieces, the chances of losing the transmission was much smaller. In case of loss of connectivity, the transmission could be restarted from that part. The process was slower but much more reliable. It also allowed people who accessed the Internet only for email, using dial-up lines, to download files that were located remotely, and even if they weren't actually connected online to the Internet (for example, using BBSs or other specialized e-mail software).
Popular examples were the servers located at universities such as ftpmail@sunsite.unc.edu and bitftp@pucc.princeton.edu, which hosted repositories containing the earlier versions of Linux and other GNU software. Access to these repositories via FTPmail was instrumental at allowing people from foreign countries to try to adopt these tools at a time where online connectivity was impossible.
FTPmail services were common in the 1990s, but have dwindled in importance as FTP lost popularity in favour of other methods for file transfer, notably HTTP which is available to virtually all Internet users.
Procedure
An emailEmail
Electronic mail, commonly known as email or e-mail, is a method of exchanging digital messages from an author to one or more recipients. Modern email operates across the Internet or other computer networks. Some early email systems required that the author and the recipient both be online at the...
is sent to a FTPmail server with the command to be performed, inserted as the body of the message. The server then processes the request by logging on to the remote site and returning the result via email.
Basic commands used
| Command | Function |
|---|---|
| help | Returns a help file. |
| Connect to site. | |
| cd path | Change directory to path specified. |
| List the contents of the directory. | |
| List the contents of the directory | |
| get file | Get a file, the path to save can also be *mentioned. |
| size is Kb>Mb. | |
| mode binary | Binary mode: archives, binary files. |
| mode ascii | ASCII mode: nothing but ASCII text. |
| quit | End of ftp-by-email message. |