Internet Guides: FTP What is FTP? File Transfer Protocol a method by which files are moved between computers on the Internet. The most common type of FTP is anonymous ftp, by which anyone can transfer files from publicly accessible portions of more than 1500 computers on the Internet to their personal computer or computer account. What can I find using FTP? Many thousands of text files and archives covering almost every conceivable subject; software programs; electronic books and journals; images of paintings, photographs, and artwork of various kinds; sound files; HyperCard stacks; courseware; etc. There are over 2 million different files available for anonymous FTP and the number grows every hour. How can I use FTP? To use FTP you must first be using a computer that is connected to the Internet, such as Vanderbilt’s CTRVAX, whether it be by direct link or modem. If you want to download files from your CTRVAX account to your own computer’s hard disk then you must also have the correct communications software, such as PacerLink (for Macs) or Kermit (for PCs). You will also need special software for decompressing and decoding some files. Contact the Vanderbilt University Computing Center (VUCC) at 343-1631 for more information on obtaining and using these programs. How do I find out which computer has the files I need? There are several ways to locate FTP files on the Internet. If you know the name of the files you are looking for, or can guess at a likely filename for what you want, then you can use another Internet tool called Archie. Archie searches all available FTP sites once a month and creates a database of what it finds; you can then search the Archie database with word strings and find out which computer has files that match your search terms. See Internet Guide: Archie for more instruction on using Archie. FTP sites are often mentioned in Listserve discussion groups or Usenet newsgroups, particularly in FAQ files. Many gophers also provide lists of FTP sites. FTP Etiquette: Remember that when you are using FTP, you are using another institution's computer. Keep your FTP sessions as short as possible and always try to avoid using a site during working hours (8-5 their time). Do not use FTP sites outside of North America unless absolutely necessary. Many FTP sites can also be accessed using Gopher, which also allows file transfer, and this is preferred when possible. Gopher does not use as much of the host computer's resources. What are the FTP commands? To start the FTP program on the CTRVAX, type ftp. You will then see the ftp> prompt and are ready to enter the address of the host computer you wish to connect to. Once connected to the remote computer you are under the remote computer’s control and using its FTP program. The commands for most FTP programs are the same. The following are the most common commands and will work with Vanderbilt’s CTRVAX: ftp start FTP session open access the named FTP host. (type open then the host computer's address) dir display list of files in current directory cd change directory cd.. change directory up one level ascii prepare for text-only transfer (default setting on most machines) binary prepare for binary file transfer get filename copy a file from the host computer to your computer bye closes connection to remote host , but leave FTP open exit end FTP session (returns to $ prompt) help list FTP commands FTP Site Directory structure: Most FTP hosts are organized in the same way as DOS directories or Mac folders: in a hierarchical file system with directories, subdirectories, and files. Directory paths are usually cited as directory/subdirectory/file. Us the cd command to move from level to level till you reach the file you need, then use the get command to transfer the file to your computer. What does a typical FTP session look like? The following is a record of an FTP session that transfers a text file (internet-tools.txt) and a binary file (internet-tools.gif) from the host computer ftp.rpi.edu to an account on VU’s CTRVAX. The files we are looking for are in the pub/communications directory. Words in bold are commands you type in. Contact VUCC at 343-1631 if you have trouble initiating or completing an FTP session. $ $ ftp ctrvx1.Vanderbilt.Edu MultiNet FTP user process 3.2(106) FTP>open ftp.rpi.edu Connection opened (Assuming 8-bit connections) cd pub cd communications dir get internet-tools.txt binary Type: Image, Structure: File, Mode: Stream NETSERV1.ITS.RPI.EDU>get internet-tools.gif bye and you are ready for connection to another host or you can type exit to return to the CTRVAX $ prompt. Why don’t the files I get work? (Or, what do binary, ACSII, compressed, archived, zip, and binhex all mean?) The hardest part of FTP is often utilizing a file once you have transferred it to your computer. If you have downloaded a text file, you might not be able to read it, or if it is a software file, you can’t make it run. There are two primary reasons why you might have such a problem: 1. Transfer type ASCII or binary? When using FTP you have to tell your computer whether the file you are getting is ASCII or binary. ASCII is a text-only format and is the default for the CTRVAX system. ASCII filenames most often end with .txt. Binary files are non-text files stored in binary code such as software programs, sound files, or compressed or archived files. 2. Compressed files? Many text and binary files are compressed using special software programs that make the files smaller so that they take up less space on the host computer and also so they can be transferred faster. You must have the appropriate software to decompress the file. There are different programs for DOS machines, Macs, or UNIX. Contact VUCC for help in locating and using decompression software. Why can't I get the files I ask for? Be aware that many FTP site's host software is case sensitive. If you have trouble getting a file, be sure that you have typed in the file name exactly as it is typed in the directory list or the written reference you have to the file. Check the site for ReadMe files for specific information on correct command configurations. Contact VUCC at 343-1631 if you continue to have trouble. This guide was adapted from a handout produced at the University of Texas at Austin General Libraries. Prepared by Gary Parker, Education Library, Vanderbilt Univ. January 1994