The File Transfer Protocol

Like the Telnet server, Windows NT/2000/2003/XP comes through Windows Server 2003, the FTP server is providedwith an FTP client. For Windows NT 4.0 by installing Internet Information Services

The FTP Client

The FTP client can be utilized easily from the Command Prompt and uses the standard syntax that's common to other FTP clients, with a few exceptions that you might not notice. For example, although many Unix/Linux servers require that you log in by using the command User , the Windows version prompts you for the username after you issue the FTP command as well as the password for the account name you enter. This is a minor difference, but it's important to note that although FTP is defined by a set of RFCs, some vendors add their own features to make the utility simpler to use.

The FTP server for Windows NT through Windows Server 2003 is a component of IIS, which is included as part of the installation procedure for Windows 2000. For Windows NT, you can use the icon that appears on the desktop of a Windows NT Server to install IIS or, better yet, download the newest version from Microsoft. IIS has been enhanced many times since its first release. Windows 2000 Server users will find that IIS is included on the server installation CD, but again, check for a newer version at Microsoft's Web site. An important reason for this is that newer versions have fixed problems with previous ones. Of course, the reverse is also true in some cases. One problem is fixed by a newer version, but might introduce a new set of problems!

Another method for logging into many sites is to use the username anonymous. The convention for using this login is to use your email address for the password prompt. After you've logged in to the FTP server, you can issue commands that are available on that server. For example, the commands is and dir will usually produce a listing of files and directories for the main directory that's set up for your login type. When using Unix/Linux or Windows clients, you can use the CD command to change to another directory until you find the data that you need to use. Notice that for most implementations of FTP, you must use lowercase characters for the commands and use the exact lowercase or uppercase syntax for a particular file. You can then use commands such as the following:

• get—Use this command to retrieve a file from a remote server. For example, get filename.
• put—Use this command to send a file to a remote server. For example, put filename.
• mget—This command can be used with wildcards (such as * and ?) to retrieve multiple files that match the wildcards.
• mput—This command works like mget, but enables you to send multiple files to the FTP server using wildcards.
• hash—If you care to watch the progress of an operation such as sending or receiving a file, this command will print hash marks (#) to show you the progress of the operation.
• binary/ascii—These commands specify the type of file you want to receive or send. ASCII files consist of simple text files, whereas binary files are usually executable files (application files, word processing files, and so on).
• prompt—This command might not be available on all implementations of FTP. This command is generally used with the mget or mput commands. When using these commands with wildcards, you might be prompted to specify yes or no (Y/N) before sending a file. The prompt command eliminates these prompts and just downloads or uploads all files matching the file specification.
• quit—This command is used to exit the FTP client.

Tip

Wildcards are used by many operating systems to indicate that you're specifying certain characters that a filename must contain and at the same time specifying that other characters can be anything. The asterisk (*) wildcard means that any characters (and any number of characters) can be substituted for the filename. For example, using the filename of Yoko*.txt will retrieve (or send) any file that starts with Yoko, ends with .txt, and contains any number of characters between Yoko and the dot 1.1 delimiter.

Another wildcard, the question mark (?) can be used to specify a specific number of characters that can be used to match a get or put operation. For example, the filename sec ret???.txt means that the file must start with the text secret and be followed by just three characters and the filename extension .txt. Contrast this with the * wildcard which allows for any number of characters following those you specify.

Additionally, you can specify the * wildcard in a manner such as *.mpeg2 to send or receive any file that ends with the file extension of . mpeg2, no matter how many characters make up the first part of the filename. The same goes for using the ? wildcard, although it still specifies that only filenames that contain the same number of question marks will be sent or retrieved