SSH Key: RSA vs Ed25519

Comparison

• Ed25519: Shorter key, but may not be supported on old SSH server
• RSA: widely used, but require at least 4096 bits in key length

Generate Ed25519 Keys

ssh-keygen -t ed25519 -f ~/.ssh/your-key-filename -C "your-key-comment"

Reference

• SSH Key Best Practices for 2025 – Using ed25519, key rotation, and other best practices’
• How do Ed5519 keys work?
• 選擇 SSH key 的加密演算法