File Transfer Protocols

These protocols are used to transfer files across networks, offering different levels of security, reliability, and platform support.

Protocol

Description

Use Case

FTP (File Transfer Protocol)

Standard protocol for transferring files over TCP, but lacks encryption. Widely used but not secure unless combined with tunneling or encryption layers.

Internal file transfers in trusted networks.

FTPS (FTP Secure)

FTP over SSL/TLS encryption for secure data transmission. Encrypts both commands and data — supports certificates and secure authentication.

Secure file transfer over the internet.

SFTP (SSH File Transfer Protocol)

File transfer protocol over SSH. Provides full encryption and secure authentication.

Secure transfers and remote file management over SSH.

SCP (Secure Copy Protocol)

Simple and fast file transfer over SSH. One-way secure copy; lacks advanced features like resume or GUI.

Quick secure file copies between Unix/Linux systems.

TFTP (Trivial File Transfer Protocol)

Lightweight file transfer without authentication or encryption. Used in LANs and for bootstrapping network devices (e.g., PXE).

Transferring firmware or boot images to devices.

NFS (Network File System)

Allows shared access to files over a network, mainly in Unix/Linux systems. Mounts remote file systems as if they were local.

Centralized file storage and sharing within a network.

RFC: RFC 959

Main Features:

  • Standard protocol for file transfers over TCP (ports 20 and 21)

  • Allows file upload/download, directory navigation, and file operations

  • Does not provide encryption for commands or data

  • Supports anonymous and authenticated access

  • Widely supported across operating systems

Use Cases:

  • Internal file transfers in trusted networks

  • Legacy systems and applications that require FTP support

  • Bulk data upload/download in low-security environments

Alternative Protocols:

  • FTPS – FTP with SSL/TLS encryption

  • SFTP – Secure file transfer over SSH

  • SCP – Simple, secure file copy

  • TFTP – Lightweight transfers for device booting

RFC: RFC 4217

Main Features:

  • FTP enhanced with SSL/TLS encryption for control and data channels

  • Supports secure authentication with certificates or credentials

  • Explicit (AUTH TLS) and implicit encryption modes available

  • Compatible with many FTP clients and servers

Use Cases:

  • Secure file transfer over public or untrusted networks

  • Compliance-driven environments requiring encryption (e.g., PCI-DSS)

  • Secure publishing of data or logs to external partners

Alternative Protocols:

  • SFTP – Secure alternative with simpler firewall handling

  • SCP – Lightweight secure copy with fewer dependencies

  • HTTPS-based file transfer portals

RFC: Part of SSH-2 protocol (Draft Standard)

Main Features:

  • File transfer protocol built on SSH (port 22)

  • Provides strong encryption and authentication

  • Supports remote file manipulation (rename, delete, permissions)

  • Resistant to packet sniffing and man-in-the-middle attacks

Use Cases:

  • Secure file transfers and automation (cron jobs, CI/CD)

  • Remote file management over secure tunnels

  • File exchange with servers over the internet

Alternative Protocols:

  • SCP – Simplified file transfer over SSH

  • FTPS – FTP with SSL/TLS

  • rsync over SSH – For incremental file syncing

RFC: None (based on SSH)

Main Features:

  • Secure, fast file transfer protocol using SSH (port 22)

  • Simple syntax for single-session transfers

  • Lacks features like resume, progress tracking, or directory listing

  • Available on most Unix/Linux systems by default

Use Cases:

  • Quick secure file copies between Unix/Linux systems

  • Simple remote backups or file pushes

  • Transferring files in automated SSH scripts

Alternative Protocols:

  • SFTP – Feature-rich secure file transfer

  • rsync – Efficient file sync and transfer over SSH

  • FTPS – Secure alternative using standard FTP architecture

RFC: RFC 1350

Main Features:

  • Very simple file transfer protocol over UDP (port 69)

  • No authentication, encryption, or directory support

  • Ideal for constrained environments or bootstrapping

  • Limited to read/write of preconfigured files

Use Cases:

  • Transferring firmware or boot images (e.g., PXE boot)

  • Embedded systems and networking devices

  • Simple LAN-based file delivery without user interaction

Alternative Protocols:

  • FTP – For more complex file transfers

  • NFS – For persistent file sharing in local networks

  • HTTP/HTTPS – For firmware distribution with progress/validation

RFC: RFC 1094 (v2), RFC 1813 (v3), RFC 7530 (v4)

Main Features:

  • Distributed file system protocol for sharing directories/files over LAN

  • Allows remote mounting of file systems as if they were local

  • Stateless (v2/v3) or stateful (v4) client-server architecture

  • Supports file locking, permissions, and access control

Use Cases:

  • Centralized file storage across Unix/Linux systems

  • Home directory sharing in enterprise and academic environments

  • High-performance computing clusters with shared data

Alternative Protocols:

  • SMB/CIFS – Windows-based file sharing

  • WebDAV – HTTP-based file system access

  • FTP/SFTP – For simpler file-based transfers