{"id":29347,"date":"2021-02-23T09:38:52","date_gmt":"2021-02-23T17:38:52","guid":{"rendered":"https:\/\/careerkarma.com\/blog\/?p=29347"},"modified":"2021-03-29T04:22:10","modified_gmt":"2021-03-29T11:22:10","slug":"what-is-ftp","status":"publish","type":"post","link":"https:\/\/careerkarma.com\/blog\/what-is-ftp\/","title":{"rendered":"What is FTP?"},"content":{"rendered":"\n

File Transfer Protocol, or FTP, is how files are transferred between computers on the Internet. It is a safe and reliable way to send files between users with access to the FTP server. FTP is also a common method for updating files on websites. 
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FTP was developed in the 1970s by MIT student Abhay Bhushan. Initially, Bhushan created FTP to securely transfer files over a network called ARPANET. This program was the precursor to what we now consider the modern web. 
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In order for a File Transfer Protocol session to be created, a user is granted access to the FTP server with credentials. Essentially, a user signs in to the FTP server and is able to start transferring files. An exception to this practice is called anonymous FTP, where a public FTP server, which does not require credentials, is used.<\/p>\n\n\n\n

How Does FTP Work?<\/h2>\n\n\n\n

As stated above, a user will have to provide credentials to gain access to the FTP server. Once access is granted, the user sends a request to the FTP server to create changes on that server. With access granted, the files are transferred. 
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The transfer process occurs on two channels of communication: the command channel and the data channel. The command channel initiates a request and response to and from the FTP server. The data channel is responsible for distributing data. 
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A user\u2019s command channel contacts the server\u2019s command channel to initiate a request. The server sends a response back to the user\u2019s command channel. Then, the server sets up a connection between its own data channel and the user\u2019s data channel specified in the request. Now, the user can transfer data through the data channel. 
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The above example illustrates what is known as an active mode FTP session. A common issue with active FTP is firewall blockage. This occurs due to the fact that the user request is not an actual connection to the server. Rather, it is a reference to the server\u2019s port. When the server responds by making the connection to the user\u2019s port, a firewall alert can block the connection. 
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A passive mode FTP was developed to address the issue of the user\u2019s firewall. In a passive mode FTP, the user sends a request to the server on the command channel, much like in our active mode example above. Again, the server responds to the user\u2019s command channel, but this time it sends what port it will be listening to for the data channel transfer. 
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The port the server listens to is a random one and not its own data port. This is the major difference between active and passive modes. From the randomly assigned port, the server connects with the user\u2019s data port and begins the transfer. 
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By using a randomly assigned port on the server side, rather than its own data port, the firewall issue is bypassed. This is accomplished by having the user make both connections: command channel and data channel. <\/p>\n\n\n\n

Using FTP<\/h2>\n\n\n\n

Now that we know what FTP is, how can we use it? The most common way to use FTP is through an FTP client. An FTP client is a program that transfers files to computers and servers. A reliable FTP client has the ability to securely transfer large files in a short amount of time. 
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Some popular FTP clients include:<\/p>\n\n\n\n