The 10-Round Process
Initial
AddRoundKey with Key₀
Round 1
SubBytes → ShiftRows → MixColumns → AddRoundKey
Round 2
SubBytes → ShiftRows → MixColumns → AddRoundKey
Rounds 3-9 repeat the same pattern
Each with a unique round key
Each with a unique round key
Round 10
SubBytes → ShiftRows → AddRoundKey
(No MixColumns in final round)
(No MixColumns in final round)
Lightning Fast
AES processes billions of operations per second. Modern CPUs have hardware acceleration (AES-NI) making it even faster.
→ Millions of 16-byte blocks/second
Quantum Resistant
Grover's algorithm could theoretically reduce AES-128's strength to 64-bit security—but this still requires millions of qubits and is impractical for decades. AES-256 drops to 128-bit post-quantum strength, matching today's AES-128 security.
→ 2¹²⁸ possible keys = 3.4 × 10³⁸ combinations
Exponential Strength
Multiple rounds with unique keys compound the security. Each round exponentially increases the difficulty of breaking the cipher. AES-256 uses 14 rounds for even greater security.
→ AES-128: 10 rounds | AES-256: 14 rounds = military-grade encryption