2. Ports and Protocols: SSH, HTTP, HTTPS, FTP/SFTP and DNS
2.5 FTP and SFTP
FTP juna protocol aahe – aajun kahi hosting companies vaprtat. Pan tyacha motha problem: username aani password clear text madhe jatat.
| Point | FTP | FTPS | SFTP |
|---|---|---|---|
| Port | 21 (control) + 20 or random (data) | 21/990 + data ports | 22 (runs over SSH) |
| Encryption | None | TLS | SSH |
| Firewall friendliness | Poor (extra data ports) | Poor | Good (one port) |
| Recommended? | No | Only if required | Yes |
sftp -i mykey.pem ec2-user@<PUBLIC_IP> # then: put file.txt, get file.txt, ls, bye
scp -i mykey.pem report.pdf ubuntu@<PUBLIC_IP>:~/
Why this matters for security
With Wireshark (Part 10) you will literally see an FTP password appear in the packet capture. Anonymous FTP login and old vulnerable FTP servers (Metasploitable 2 runs one) are classic lab targets. In real systems, replace FTP with SFTP/SCP over SSH.
Ravindra Bagale's Tip
Khup students EC2 var file upload karayla vsftpd install kartat aani port 21 open kartat. Garaj nahi! SSH already chalu aahe – WinSCP, FileZilla kiwa MobaXterm madhe protocol "SFTP" nivda, port 22, aani tumchi key dya. Ek kami port open, ek kami dhoka.
Practice task
Connect to any Linux machine with sftp, upload a file, list it, download it back, and exit with bye.