Introduction to FTP

• Using a Web Browser to download files from a web site
• Using a Web Browser to download files from an FTP site
• Using an FTP client to download a file from an FTP site.

• Purpose Application for copying files from one computer to another over a network.
• Features
  • Platform & File Format Independent
  • Mechanisms for transfering both compressed archive files & uncompressed files & binaries (executable programs).
  • Group (directory) transfer
  • Remote file management
• Miscellaneous
  • FTP uses the TCP/IP Based Protocol (packet networks not handshaking)
  • Not usually available on Commercial Networks & Bulletin Boards
  • Requires Internet name of remote computer to connect to
  • Not designed as a file searching tool but as a file accessing tool
  • For faster transfer, files are generally compressed, so to download from archives you need a decompression utilities
  • FTP is now embedded in most World Wide Web browser applications
• Free Access
  Many sites provide free access to a special account which anyone with FTP can get into to put files, or as it is more often the case, get files such as graphics, freeware, or shareware. These anonymous login services provides no cost access to all Internet users. Not available on all Internet machines.
• Usage
  
  • Passwords
    To log onto an account, even an anonymous FTP accont, you need to provide a password. Nettiquette (Internet Ettiquette) suggests that you use your email address as the connection password.
  • Limits
    Many sites limit the number of anonymous connections to insure adequate response time (service). Connections to heavily subscribed sites should be limited to non-business hours due to their heavy loads.
  • READMEs
    Most sites have README files which should be downloaded & read these to learn the sites access procedures.
  • Mirrors
    Popular sites which are unaccessible often send mirror site lists. Mirrors are other Internet machines that have the exact same files.

• Connecting to a Remote Site
  • UNIX FTP

    fir.cs.vt.edu> ftp info.cs.vt.edu
    Connected to info.cs.vt.edu.
    220 info.cs.vt.edu FTP server (Version wu-2.1c(30) Thu Oct 21 09:31:58 EDT 1993)
     ready.
    Name (info.cs.vt.edu:barnette): anonymous
    331 Guest login ok, send your complete e-mail address as password.
    Password:
    230 Guest login ok, access restrictions apply.
    Remote system type is UNIX.
    Using binary mode to transfer files.
    ftp>_
     

  • Mac FTP (Fetch)
  • Window FTP (Ws Ftp)

• Transfer Modes The transfer mode is the format that your FTP application expects the files to be transfered in. There are generally two types of formats: ASCII (text-based) or binary (machine or computer type specific). Most FTP clients also have an automatic setting that picks the transfer mode based on what it thinks it should be.
  • ASCII

    ftp> ascii
    200 Type set to A.
    ftp>_
     

  • Binary (MacBinary)

    ftp> binary
    200 Type set to I.
    ftp>
     

• Navigation Some UNIX navigation commands.
  • ftp>cd directory change directory
  • ftp> lcd directory local change directory
  • ftp> ls directory listing
  • ftp> dir directory listing
  • ftp> mkdir make directory
  • ftp> rmdir remove directory

  ---

  
  
• UNIX FTP Session
  

  ftp> pwd
  257 "/pub" is current directory.
  ftp> ls
  200 PORT command successful.
  150 Opening ASCII mode data connection for file list.
  incoming
  DigitalLibrary
  reports
  reportd.log
  226 Transfer complete.
  ftp> cd DigitalLibrary
  250-Please read the file README.DLSB
  250-  it was last modified on Thu Apr  7 16:01:19 1994 - 176 days ago
  250 CWD command successful.
  ftp> ls
  200 PORT command successful.
  150 Opening ASCII mode data connection for file list.
  DLSB-TOC.doc
  DLSB-TOC.ps
  DLSB-Titlepage.frame
  DLSB-Titlepage.ps
  DLSB-ch1-7.frame
  DLSB-ch1-7.ps
  DLSB-index.doc
  DLSB-index.ps
  DLSBch1.ps
  DLSBch2.ps
  DLSBch3.ps
  DLSBch4.ps
  DLSBch5.ps
  DLSBch6.ps
  DLSBch7.ps
  README.DLSB
  226 Transfer complete.
  ftp>prompt
  Interactive mode off.
  ftp>_
  

   

  ---

• Downloading Files
  • ftp> get filename

    ftp> get README.DLSB
    200 PORT command successful.
    150 Opening BINARY mode data connection for README.DLSB (3355 bytes).
    226 Transfer complete.
    3355 bytes received in 0.002 seconds (1.7e+03 Kbytes/s)
    ftp>_
     

  • Mac FTP (Fetch)
  • Window FTP (Ws Ftp)

• Uploading Files
  • ftp>put filename
  • ftp> mput *

    ftp> mput *
    local: fexist.c remote: fexist.c
    200 PORT command successful.
    150 Opening BINARY mode data connection for fexist.c.
    226 Transfer complete.
    332 bytes sent in 0.0039 seconds (83 Kbytes/s)
    local: fexist.doc remote: fexist.doc
    200 PORT command successful.
    150 Opening BINARY mode data connection for fexist.doc.
    226 Transfer complete.
    604 bytes sent in 0.0029 seconds (2e+02 Kbytes/s)
    local: fexist.h remote: fexist.h
    200 PORT command successful.
    150 Opening BINARY mode data connection for fexist.h.
    226 Transfer complete.
    168 bytes sent in 0.0039 seconds (42 Kbytes/s)
    ftp>_
     

Further Exploration

• SquareOne's How do I Install and Use a FTP client
• C|Net ShareWare
  
• FTP FAQ
  
• FTP Help
  

Author: N. Dwight Barnette
Curator: Computer Science Dept : VA TECH. (c) Copyright 1994.
Last Updated: 1/15/97/I>