9 Apr 1995
The File Transfer Protocol is the oldest and simplest of the Internet services. Throughout the world, volunteer machines provide archives of programs that run on every type of operating system and data files on all sorts of topics. FTP transfers a file through the network much like the COPY command transfers a file from one disk to another.
When an organization makes a group of files available to everyone on the Internet, the arrangement is called "Anonymous FTP". The name derives from the convention of supplying a the dummy name "anonymous" in the field for a userid. The password field should then contain the E-Mail address of the requesting user.
FTP also allows someone with a real account on the server machine to present a valid userid and password and gain remote access through the network to the same files and directory that the user would be authorized to use through an ordinary local or terminal logon.
Frequently, a user has a partial or complete file name and needs to locate an FTP server from which the file may be obtained. The Archie service provides the answer. The user fills in the available information to a front-end program, which passes the request to an Archie server. Nightly the Archie servers survey FTP servers through the network to maintain a database of available files. The Archie server consults the database, and sends back a listing of the servers and directories containing files that meet the description.
In the Windows environment, WS_FTP sets a high standard for FTP client programs. Though freeware, it is as good as the FTP client in any commercial product.
The versions of WS_FTP are generally identified by their release date. The 940911 identifies this as the version built for distribution on Sept 11, 94. All versions are distributed as WS_FTP.ZIP, although the newest version while it is being tested is often posted as WS_FTP.ZIP.BETA.
Click here to view the directory at West Point that contains WS_FTP. You may fetch the file from there and save it to disk.
The first time WS_FTP is started, it prompts for your E-Mail address. This string will be used as the password for anonymous FTP access to public servers.
WS_FTP can be launched with parameters that cause it to connect to a specific server and fetch a specific file. This is used for internal linkage by programs such as WSARCHIE that use WS_FTP as a support tool. Normally, however, the user will launch the program without parameters, and it will present a panel that allows the user to select from a list of preconfigured host computers, or to add a new host to the list.
WS_FTP is distributed with an INI file that identifies the distribution points for the most popular Windows Internet programs, and for WS_FTP itself. There is a bootstrapping process here. Find any old version of WS_FTP, load it and start it, and the first option you are given is the opportunity to load the latest and greatest release through the network.
To create a new entry, click the button labeled New to empty the fields. The options presented here have come to be universal among GUI-ish FTP programs. The remote host is given an alias and is identified by an IP number or domain name. To access public files, click the box labeled Anonymous Login and the program fills in the userid and password field. It is possible to configure a starting directory both on the remote computer and on the local client. The Account field is needed for mainframe servers running IBM's VM operating system.
FTP is actually a special purpose terminal logon to the remote host. The original assumption was that a human user would read the responses and make selections by entering commands. The commands are standardized, but the responses that the server sends back vary from system to system. After all, the information in a directory listing changes from one operating system to another. WS_FTP can identify most types of servers. If the automatic identification fails, a particular Host Type can be selected from the list box.
Once the connection is established, a list of local files (on this computer) is shown of the left and a list of remote files (on the server) is shown on the right. Subdirectories are in the top box, and files are below them. Clicking on a subdirectory entry does a CD and updates the list. Select a file and click one of the buttons.
The "< --" button copies a selected remote file (on the right) from the server to the current local directory. The "--> " button copies a selected local file (on the left) to the remote server (and requires that you have permission to write files to the remote server). The ASCII and Binary buttons determine the type of transfer.
Different types of computers have different conventions for ending a line of text. A PC ends each line with two characters CR (Carriage Return) and LF (Line Feed). Unix systems only use LF and Macintosh systems only use CR. There are two types of file transfer. Click the "Binary" option to transfer programs and archives (ZIP files). Binary will also transfer text files correctly IF the remote server is some type of PC (a Windows NT or OS/2 server). However, to get text files from other systems transferred correctly, click the "ASCII" option.
The buttons along the side of the two directory listings perform operations on the local disk files or the remote files. The remote server must grant permission to write to its disk, and public servers will not allow this. However, a user can use FTP to create and delete files and directories on a mainframe computer or workstation where he or she has an account.
The Button marked View reads a text file in and displays it with the Windows Notepad utility. This is useful for examining README or INDEX files before deciding what to load. The button marked Exec reads the file in and then processes it with whatever utility program is associated with its file type in the Windows File Manager. For example, using Exec with README.WRI would load the Windows Write program, README.TXT would go to Notepad, README.DOC would go to Word, and README.HLP would be displayed as a Help file.
Sometimes it is helpful to see the full directory listing including file sizes and dates. The DirInfo button launches Notepad to display it.
Along the bottom, the Close button terminates the connection to the current server. The button then becomes a Connect button that will trigger the connection dialog to select another server.
Public libraries of programs and files are stored in "archive" format. Today, ZIP is the most popular format. Originally, such files were stored in the ARC format, a ZIP precursor. The network tool for finding an archive file when you know part of the name, but you don't know the server, is a system called Archie. Archie servers are located throughout the world. At night, when the network traffic drops off, they poll registered public libraries for information about updated files. This is stored in a database. An Archie client supplies the server with a complete or partial file name, and the server sends back a list of file servers that match.
The client selects the nearest server from the dropdown list labeled Archie Server. Type the partial or complete file name in the Search for box. Press the Search button. The results are displayed in the boxes below. The Hosts list shows the set of file servers that have at least one file matching the search string. When a host is selected, the Directories list shows the set of directories on that host that have files. When a directory is selected, the set of Files is displayed on the right. The Options menu allows the user to configure access to WS_FTP and a target directory. When this is done, clicking on a file launches WS_FTP to transfer the remote file to the local system.
The preferred server is not always available, or it may refuse new requests when the maximum number of users are connected. The combination of WSARCHIE and WS_FTP provide a simple method of locating a backup source for the same information.
Click here to view the directory where WSARCHIE is normally distributed.
Although WS_FTP will run in the Windows environment of OS/2, there are advantages to a native FTP client that can make use of the more powerful Internet program interface available in OS/2 and can creatively use multitasking. An FTP tool is available as part of the NetSuite package. This is a shareware program which, after an evaluation period of 30 days, should be registered at a cost of about $35.
Once the NetSuite FTP program is launched, it leaves a Toolbar on the screen. The first icon (which represents the plug on the end of a cable) stands for "Connection" and launches the dialog for a new session with a different remote host. Unlike WS_FTP, it is possible to have more than one connection active at a time. It is even possible to be transferring several files to or from several hosts simultaneously.
The Connection dialog presents a list of configured host computers. The user can select one of the existing hosts, or can click the Add button to create a new entry. Pointing to an entry and clicking the second (right) mouse button brings up the existing definition to edit it. The definition of a remote host is similar to the corresponding operation in WS_FTP.
As with WS_FTP, the local files are on the left and the remote files are on the right. However, the NetSuite program operates in the OS/2 style of display. The default shown here is "details" mode, although it is also possible to display in Icon mode (like a Mac) or Name mode (like Windows File Manager). Select a file and click the right button to bring up a menu, as shown here on the right. A file can be transferred by selecting Get on the menu or the Get Toolbar button. It is also possible to "drag and drop" the file icon from the one side to another. Files can be transferred to the remote host using the Put operation if you have the proper authority to create files there.
During file transfer, the utility presents a bar graph across the top indicating progress. There is also a byte count and a real-time calculation of the data transfer rate (in this case, 1.55K bytes per second over a 14400 modem running SLIP).
NetSuite FTP demonstrates many of the advantages of OS/2 over Windows. It is possible to connect to more than one host at a time and to transfer several large files simultaneously. If you make a mistake, a transfer can be canceled reliably, without leaving the Internet connections in some bad state. The real-time display of transfer rate is quite useful comparing the performance of various remote servers. Although there is a 32-bit version of WS_FTP, it does not exploit the opportunities of NT or Chicago to the same extent.
Click here to fetch the NetSuite package (set your browser to save it to disk).
IBM's TCP/IP for OS/2 contains a built-in FTP server. Windows NT also contains an FTP server that runs in the background. The NT server is nicely integrated with the native operating system security mechanisms. The IBM server creates its own stupid unencrypted password file. In this, as in other cases, NT provides a better platform for network server functions.
Continue Back PCLT
Copyright 1995 PC Lube and Tune -- Windows on the World -- H. Gilbert