Skip to main content

Table 2 Symmetric-key CS-based cryptosystem

From: On the security of compressed encryption with partial unitary sensing matrices embedding a secret keystream

Public Subsampling operator R Ω
  Unitary matrices U 1 and U 2
  Structure of a keystream generator
Secret Initial seed (or state) k{0,1}L of a keystream generator
Keystream generation With the initial seed k, a keystream s{−1,+1}N is generated. The keystream s is renewed at each encryption.
CS encryption With the keystream s and a plaintext \(\mathbf {x} \in {\mathbb {R}}^{N}\), a ciphertext is generated by \(\mathbf {r} = \boldsymbol {\Phi } \mathbf {x} + \mathbf {n} \in {\mathbb {R}}^{M} \), where \(\boldsymbol {\Phi } = \frac {1}{\sqrt {MN}} \mathbf {R}_{\Omega } \mathbf {U}_{1} \text {diag} (\mathbf {s}) \mathbf {U}_{2}\) and n is a measurement noise.
CS decryption The plaintext x is reconstructed by a CS recovery algorithm with the knowledge of s.