FTP (File Transfer Protocol)

File Transfer Protocol (FTP) is a fundamental protocol for transferring files between computers over a network, most commonly the Internet. It provides a reliable and efficient means of exchanging data, making it an essential tool for various industries and users.

Whether you are a web developer uploading website files, a business exchanging sensitive information with clients, or an individual sharing files with friends, FTP simplifies the process of moving data from one location to another. 

How FTP works

FTP operates on a client-server model, where one device acts as the FTP server, responsible for storing and providing access to files, and another device acts as the FTP client, requesting and receiving files from the server. This protocol relies on standardised FTP commands and responses to facilitate file transfers.

FTP commands and responses

FTP clients communicate with the server using a series of commands to perform various file operations. Some commonly used FTP commands include "USER" to provide login credentials, "PWD" to display the current working directory, "LIST" to view the contents of a directory, "GET" to download a file from the server, and "PUT" to upload a file to the server. After receiving a command, the FTP server responds with a three-digit code, indicating the success or failure of the operation, along with a message providing additional information. 

Active vs. passive FTP mode

During an FTP transfer, two modes can be used for data connections: active and passive. The FTP server initiates a data connection to the client's specified data port in active mode. In contrast, the passive mode involves the client initiating the data connection to the server's specified data port. Passive mode is commonly used when the client is behind a firewall or NAT (Network Address Translation) device, as it allows for more flexible data transfers.

Understanding how FTP commands function and the differences between active and passive modes is crucial for efficient and secure file transfers.

FTP in web development

File Transfer Protocol is pivotal in web development, facilitating the seamless transfer of website files between local systems and remote web servers. 

Uploading website files via FTP

Developers often work on their local machines when creating or updating a website before deploying changes to the live web server. FTP provides a reliable and straightforward method for uploading website files to the server. By using an FTP client, developers can connect to the remote server, navigate to the appropriate directory, and upload their HTML, CSS, JavaScript, and other necessary files to make the website accessible to users. 

Deploying website changes with FTP

Once developers have made changes to a website, whether a simple update or a major overhaul, FTP allows them to deploy those changes to the web server efficiently. By uploading only the modified files, FTP minimises the transfer time and ensures that the website is up-to-date and functional for visitors.

Using FTP for backup and restoration

FTP is a valuable tool for website backups and restoration. Regularly backing up website files to a secure location is essential in case of unforeseen events like server failures, data corruption, or cyberattacks. Using FTP, developers can easily create backup copies of their website's files, ensuring that important data and configurations are safeguarded. In the event of an issue, these backups can be swiftly restored to bring the website back online.

Differences between FTP and other protocols

File Transfer Protocol is one of several protocols for transferring files over a network. Understanding the differences between FTP and other protocols can help you choose the most suitable option. Below, we highlight some key distinctions: 

FTP vs HTTP

FTP and HTTP (Hypertext Transfer Protocol) serve different purposes in data transfer. While FTP is explicitly designed for file transfer, HTTP is primarily used for web page retrieval and communication with web servers. FTP operates on two channels for commands and data, making it ideal for efficient bulk file transfers. At the same time, HTTP typically establishes a new connection for each request, leading to potential latency issues in file transfers.

FTP vs SCP

FTP and SCP (Secure Copy Protocol) are used for secure file transfer but employ different authentication and encryption mechanisms. FTP relies on separate SSL/TLS implementations like FTPS and SFTP to secure data during transfer. At the same time, SCP uses SSH (Secure Shell) for encryption, relying on the same secure channel as the authentication. This integration makes SCP appealing to users seeking a fast, encrypted transfer without additional software or configurations.