Drive: ẋ₁=σ(y₁-x₁), ẏ₁=ρx₁-y₁-x₁z₁, ż₁=-βz₁+x₁y₁
Response: ẋ₂=σ(y₂-x₂), ẏ₂=ρx₁-y₂-x₁z₂, ż₂=-βz₂+x₁y₂
The response system is a copy of the drive's y-z subsystem, driven by x₁. Pecora & Carroll (1990) showed that if the conditional Lyapunov exponents of the response subsystem are all negative, complete synchronization occurs: (y₂,z₂)→(y₁,z₁). This was the first controlled chaos synchronization, enabling chaos-based communications (Cuomo & Oppenheim 1993).