FTP, or File Transfer Protocol, is a kind of "postman" in the world of computers. It helps transfer files between devices, like a courier delivering packages from one address to another. Imagine you have two computers, and you want to send photos, videos, or documents from one to the other. FTP takes these files and "carries" them through a special "corridor" of communication.
This "corridor" consists of two parts. The first is the command channel, where instructions are sent: what to send, where, and how. The second part is the data channel, where the files are actually moved. Connecting to FTP happens through "doors" — ports 21 and 20, through which all this movement occurs.
To access an FTP server, you can use a login and password or a special method of anonymous access that allows you to log in without registration. If you use a login and password, the server checks whether you can access it and grants or denies access to the files.
To work with FTP, you can use special programs or just the command line, as if you were sending text commands to manage the process. In special programs like FileZilla, you can simply drag and drop files, and they will be uploaded to the server or downloaded from there.
In the command line, you use commands like get to download files, put to send them, and delete to remove unnecessary ones.
Essentially, FTP is a tool for exchanging files between devices. It can be useful if you want to upload something to a website or simply transfer files between computers located in different places.
To connect to an FTP server, you can use a login and password or log in through anonymous FTP, which does not require credentials. After a successful login, the client gains access to work with files on the server.
To interact with FTP, you can use programs with a graphical interface or the command line. Windows has a built-in FTP client, but many prefer to use third-party applications like FileZilla because they are more convenient and user-friendly.
Basic commands for working with FTP via the command line:
!: switch between FTP and the operating system;
?: display help;
append: append text to a local file;
cd: change the remote directory;
delete: delete a file;
get: download a file;
put: upload a file;
mkdir: create a directory;
quit: exit FTP.
These are just some of the basic commands that will help you work with FTP. With their help, you can upload and download files, manage directories, and terminate connections.
When FTP first came into existence, it was like an open book — logins and passwords were transmitted without encryption, making it an easy target for attackers. However, not everything is so bleak, as two solutions were devised to make file transfer more secure: FTPS and SFTP.
Cloud Armor
FTPS can be seen as an updated FTP that has donned the armor of Secure Socket Layer (SSL). Now all the data you send is encrypted before transmission. This means that intercepting and reading it is virtually impossible. FTPS was proposed as a response to the vulnerabilities of FTP in document RFC 2228.
At the core of FTPS is the classic "client-server" scheme, but with protection. There are channels for control and data transfer, and the server must prove its reliability with a public key certificate. This certificate, like a seal on an envelope, proves the authenticity of the connection. When connecting, the client checks that the certificate is signed by a trusted certificate authority (CA), and only after that does the data transfer begin.
Another feature of FTPS is the ability to use X.509 certificates. This is like a passport for your encryption: it contains keys and information about the owner. Thanks to this, your files are secure, and attackers are left with nothing.
At the Heart of SSH
SFTP can be called a cousin of FTP, but with an important addition: it uses Secure Shell (SSH) for encryption. It's like exchanging files in a castle with enhanced security. SFTP uses port 22, the same one as SSH, and can authenticate users not only with logins and passwords but also with special SSH keys.
The main difference between SFTP and FTPS is that SFTP always encrypts data, without exceptions. FTPS, on the other hand, may provide an option for encryption but does not always guarantee its use. SFTP is also more flexible, as it is closely tied to SSH, which is widely used for secure connections.
Data Defenders
So, FTPS and SFTP are two reliable ways to protect your files from malicious actors. FTPS, like a knight in armor, comes to the rescue by offering encryption through SSL. SFTP, like a martial arts master, uses the power of SSH to ensure continuous protection. The choice between them depends on your needs and preferences, but both methods serve one purpose — secure file transfer.