Key capacity region for a cellular source model

A cellular source model for key generation is proposed and studied, in which a central terminal χ₀ wishes to generate K₁ with terminal χ₁ and K₂ with terminal χ₂, respectively, via public discussion. Each terminal observes a component of a correlated source sequence. The K₁ is required to be concealed from an eavesdropper that has access to the public discussion, while the key K₂ needs to be concealed from both the eavesdropper and terminal χ₁. The key capacity region is established by showing that the cut-set upper bound is achievable.