SFTP (SSH File Transfer Protocol), FTPS (FTP Secure), HTTP/S (HyperText Transfer Protocol Secure), and AS2 (Applicability Statement 2) are all protocols used for secure file transfers, each with distinct characteristics. SFTP uses SSH for encryption and operates on port 22, ensuring secure file transfers within networks or over the internet with SSH keys or username/password authentication. FTPS, an extension of FTP, employs SSL/TLS for security, operating on port 21 for explicit FTPS and port 990 for implicit FTPS, providing encrypted data transfer with support for certificates and username/password authentication, ideal for adding security to legacy FTP systems. HTTP/S, widely used for secure web communications, uses SSL/TLS encryption on port 443, ensuring the privacy and integrity of HTTP messages and supporting various authentication methods including certificates and tokens, making it suitable for web-based file transfers and APIs. AS2, primarily used in B2B transactions for EDI (Electronic Data Interchange), utilizes HTTP/S for transport and provides encryption and digital signatures for secure, reliable, and non-repudiable data exchange over standard HTTP/S ports (80 and 443),