Anonymous FTP

FTP | Anonymous FTP

Anonymous FTP

There are various implementations of the FTP protocol available. We shall implement FTP with a program called WS_FTP Limited Edition (or WS_FTP LE), which is free for educators and non-commercial home use. (WS_FTP Pro, which is not free, is the version required for commercial use.)

Making an FTP Connection

We are going to illustrate the use of FTP by making an "Anonymous FTP Access". This means an access to an FTP server that allows "Anonymous" logins: anyone can log in and get files by FTP, whether they have an account on that machine or not. Such computers are called "Anonymous FTP Servers".
The server we are going to log into is in Finland (the Internet doesn't care very much about national boundaries!), and we are going to get a file containing some software; computer types would say that we are going to "download" a file.

Logging into the Server

Open the WS_FTP LE program by double clicking on its icon. This will bring up a Session Profile screen like that in the figure below that will let you login to the remote system.

Erase any entries in the fields of the main WS_FTP LE Session Profile window and enter the following:

In the "Host Name" field, type ftp.funet.fi (the ".fi" ending on the IP address tells us that this is a network in Finland.)
Click in the box next to "Anonymous Login" (the box should become checked)
You should now see that "anonymous" has appeared in the "User ID" field and "guest@unknown" has appeared in the "Password" field. It is considered a matter of courtesy to provide your email address when you logon for anonymous ftp. So erase "guest@unknown" and enter your own email address as the password.
Leave the other fields blank.
Click the "O.K." button.

After giving the computer sufficient time to connect, you should get a display screen that looks approximately like the one shown below. As you connect and are logged in, information returned from the server appears near the bottom of the display, just above the row of buttons.

Finding the File

The list on the left side of this screen shows the directories and files that are on your computer, and the list on the right side of the display shows the directories and files that are on the ftp server in Finland. We are now going to change directories on the server to find the file that we want to get. First double-click on the entry labeled "pub" in the right side of the display. This is a directory, and double clicking on it will open it (you can tell that it is a directory (or folder) because of the little folder symbol beside it).
Double-clicking "pub" brings up a list of directories and files that are in this directory. Scroll down and find the directory "windows". Double-click its icon to open this directory. The resulting display gives a list of files and directories inside "windows". Scroll down to the directory labeled "95" and double-click to open it. The resulting display shows a folder named "winsock"; double-click to open it. Now scroll down and find the directory "Ping". Double-click to open this directory.
At this point we are inside the directory "Ping", which is inside the directory "winsock", which is inside the directory "95", which is inside the directory "windows", which is inside the directory "pub". In computer jargon, we would say that the path to our present location is /pub/windows/95/winsock/Ping, relative to the "root" directory for the FTP server on the machine we are accessing.
In the resulting list of files there should be one called wsping32.zip. This is the file that we are going to download, so select it with one click of the mouse.

Downloading the File

Before we download, we must decide whether the file is an ASCII file, (text) or a binary file. The suffix ".zip" on the file indicates that the file contains material that has been "archived" and "compressed". In this context, "archived" means that one or more files or directories have been grouped together, and "compressed" means that the files have been rearranged so that they store more efficiently on a computer (take up less space). Such zip files are always binary files (see the discussion of compression & archiving in the Appendices).
Thus, we select the button below the two file lists called "Binary". (In many cases, the button labeled "Auto" will cause the WS_FTP LE program to make the correct selection of "ASCII" or "Binary" automatically, but if you know the format for certain it is better to specify it.)
Now you need to specify where on your computer you want to put the file you are about to download. In the list of files and directories on the left, locate and click on the folder that you want to use for the destination. If you do not see this folder in the list, double click the up arrow at the top of the list to go to the next higher level directory. (Continue until you find the folder you want and then click once on it to select.)
Now we are ready to download. Since you want to transfer the file from the server in Finland (the list of files on the right) to your computer (the list of files on the left), just click the arrow in the middle of the display, between the two lists, that points from the right list to the left list.
After a while (sometimes you may have to wait a minute or two if the server is very busy) the file should download to your computer. It may take a few seconds, or a few minutes, depending on how fast your network is and (usually most important) how busy the ftp server is. While the file is downloading, information will be displayed in the message area of the WS_FTP LE window, just below the two file lists, letting you know how the transfer is progressing.

Using the Program We Have Downloaded

If your Browser is configured properly, it should have already launched a program to uncompress and unarchive the file that you have just downloaded. There should now be an icon named Wsping32.exe in your destination folder. Double click this icon, and a window like that shown in the figure below will open. (Initially the white message area will be empty exept for some information about the program itself, and the name and ip number of your computer.)

The program you have downloaded and unzipped is named WSPing32. It can be a good trouble shooting tool. If you experience a long delay in being able to connect to a remote computer, you can use this program to check whether or not that computer is currently alive on the net. You simply enter the ip number or DNS name of the computer in the box labeled "Host" and click one of the buttons at the top of the WSPing32 window. The program will then transmit a series of control packets to the indicated remote machine. (These packets carry no data but are used by the TCP/IP protocol to initiate communications between systems.)
The program's buttons perform the following functions:

Lookup -- Sends packets and returns the "official name" and ip number of the computer. This allows you to determine the ip number for a computer if you only know its name, and vice versa.

Ping -- The program sends a series of packets, reports if each transmission is successful, and gives the round-trip transit time if a packet was received. The "Cancel" button halts the pinging of the remote machine.

Trace -- Sends a series of data packets to the remote computer; reports on the time taken for the transfer and whether or not all packets were successfully received. In addition, provides information on the route taken by the packets (i.e., what gateways the packets passed through enroute to the remote computer).

Other Features of WS_FTP LE

There are many other things that you can do with WS_FTP LE. For example, you can use it to send a file from your computer to another computer (often called "Uploading"), You may find out about these things by reading the program's help files, which may be accessed with the "Help" button at the middle bottom of the WS_FTP LE window, as illustrated in the figure below.


			FTP \| Anonymous FTP
		Anonymous FTP There are various implementations of the FTP protocol available. We shall implement `FTP` with a program called `WS_FTP` `Limited` `Edition` (or `WS_FTP` `LE`), which is free for educators and non-commercial home use. (`WS_FTP` `Pro`, which is not free, is the version required for commercial use.) Making an FTP Connection We are going to illustrate the use of `FTP` by making an "Anonymous `FTP` Access". This means an access to an `FTP` server that allows "Anonymous" logins: anyone can log in and get files by `FTP`, whether they have an account on that machine or not. Such computers are called "Anonymous `FTP` Servers". The server we are going to log into is in Finland (the Internet doesn't care very much about national boundaries!), and we are going to get a file containing some software; computer types would say that we are going to "download" a file. Logging into the Server Open the `WS_FTP` `LE` program by double clicking on its icon. This will bring up a `Session Profile` screen like that in the figure below that will let you login to the remote system. Erase any entries in the fields of the main `WS_FTP` `LE` Session Profile window and enter the following: In the "Host Name" field, type ftp.funet.fi (the ".fi" ending on the IP address tells us that this is a network in Finland.) Click in the box next to "Anonymous Login" (the box should become checked) You should now see that "anonymous" has appeared in the "User ID" field and "guest@unknown" has appeared in the "Password" field. It is considered a matter of courtesy to provide your email address when you logon for anonymous ftp. So erase "guest@unknown" and enter your own email address as the password. Leave the other fields blank. Click the "O.K." button. After giving the computer sufficient time to connect, you should get a display screen that looks approximately like the one shown below. As you connect and are logged in, information returned from the server appears near the bottom of the display, just above the row of buttons. Finding the File The list on the left side of this screen shows the directories and files that are on your computer, and the list on the right side of the display shows the directories and files that are on the ftp server in Finland. We are now going to change directories on the server to find the file that we want to get. First double-click on the entry labeled "pub" in the right side of the display. This is a directory, and double clicking on it will open it (you can tell that it is a directory (or folder) because of the little folder symbol beside it). Double-clicking "pub" brings up a list of directories and files that are in this directory. Scroll down and find the directory "windows". Double-click its icon to open this directory. The resulting display gives a list of files and directories inside "windows". Scroll down to the directory labeled "95" and double-click to open it. The resulting display shows a folder named "winsock"; double-click to open it. Now scroll down and find the directory "Ping". Double-click to open this directory. At this point we are inside the directory "Ping", which is inside the directory "winsock", which is inside the directory "95", which is inside the directory "windows", which is inside the directory "pub". In computer jargon, we would say that the path to our present location is /pub/windows/95/winsock/Ping, relative to the "root" directory for the `FTP` server on the machine we are accessing. In the resulting list of files there should be one called wsping32.zip. This is the file that we are going to download, so select it with one click of the mouse. Downloading the File Before we download, we must decide whether the file is an ASCII file, (text) or a binary file. The suffix ".zip" on the file indicates that the file contains material that has been "archived" and "compressed". In this context, "archived" means that one or more files or directories have been grouped together, and "compressed" means that the files have been rearranged so that they store more efficiently on a computer (take up less space). Such `zip` files are always binary files (see the discussion of compression & archiving in the Appendices). Thus, we select the button below the two file lists called "Binary". (In many cases, the button labeled "Auto" will cause the `WS_FTP` `LE` program to make the correct selection of "ASCII" or "Binary" automatically, but if you know the format for certain it is better to specify it.) Now you need to specify where on your computer you want to put the file you are about to download. In the list of files and directories on the left, locate and click on the folder that you want to use for the destination. If you do not see this folder in the list, double click the up arrow at the top of the list to go to the next higher level directory. (Continue until you find the folder you want and then click once on it to select.) Now we are ready to download. Since you want to transfer the file from the server in Finland (the list of files on the right) to your computer (the list of files on the left), just click the arrow in the middle of the display, between the two lists, that points from the right list to the left list. After a while (sometimes you may have to wait a minute or two if the server is very busy) the file should download to your computer. It may take a few seconds, or a few minutes, depending on how fast your network is and (usually most important) how busy the ftp server is. While the file is downloading, information will be displayed in the message area of the `WS_FTP` `LE` window, just below the two file lists, letting you know how the transfer is progressing. Using the Program We Have Downloaded If your Browser is configured properly, it should have already launched a program to uncompress and unarchive the file that you have just downloaded. There should now be an icon named `Wsping32.exe` in your destination folder. Double click this icon, and a window like that shown in the figure below will open. (Initially the white message area will be empty exept for some information about the program itself, and the name and ip number of your computer.) The program you have downloaded and unzipped is named `WSPing32`. It can be a good trouble shooting tool. If you experience a long delay in being able to connect to a remote computer, you can use this program to check whether or not that computer is currently alive on the net. You simply enter the ip number or DNS name of the computer in the box labeled "Host" and click one of the buttons at the top of the `WSPing32` window. The program will then transmit a series of control packets to the indicated remote machine. (These packets carry no data but are used by the TCP/IP protocol to initiate communications between systems.) The program's buttons perform the following functions: Lookup -- Sends packets and returns the "official name" and ip number of the computer. This allows you to determine the ip number for a computer if you only know its name, and vice versa. Ping -- The program sends a series of packets, reports if each transmission is successful, and gives the round-trip transit time if a packet was received. The "Cancel" button halts the pinging of the remote machine. Trace -- Sends a series of data packets to the remote computer; reports on the time taken for the transfer and whether or not all packets were successfully received. In addition, provides information on the route taken by the packets (i.e., what gateways the packets passed through enroute to the remote computer). Other Features of `WS_FTP` `LE` There are many other things that you can do with `WS_FTP` `LE`. For example, you can use it to send a file from your computer to another computer (often called "Uploading"), You may find out about these things by reading the program's help files, which may be accessed with the "Help" button at the middle bottom of the `WS_FTP` `LE` window, as illustrated in the figure below.