VPN Encryption Explained
From AES-256 to ChaCha20 — understand how encryption keeps your data safe and why it matters more than ever.
In this guide
What Is Encryption
Encryption transforms readable data into unreadable ciphertext using mathematical algorithms and keys. Only someone with the correct key can decrypt the data. VPNs encrypt all traffic between your device and the VPN server.
AES-256 Encryption
AES-256 (Advanced Encryption Standard with 256-bit keys) is the gold standard used by governments and military organizations worldwide. It would take billions of years for current supercomputers to brute-force a single AES-256 key.
ChaCha20 Encryption
ChaCha20 is a stream cipher used by WireGuard. It is faster than AES on devices without hardware AES acceleration (like mobile devices) while providing equivalent security. CasperVPN uses ChaCha20 with WireGuard protocol.
Perfect Forward Secrecy
Every session uses fresh keys. If one key were ever exposed, past and future sessions stay protected because no two sessions share a key.
Frequently Asked Questions
Is AES-256 still secure in 2026?
Yes. AES-256 and ChaCha20-Poly1305 are the standards used across the industry today, and no practical attack on either is known.