The equivalance operator is the inverse of the XOR operator, it's symmetric. Would this mean that it would also provide theoretical perfect secrecy just like XOR?
x ⊕ y = (x ∨ y ) ∧ ¬ (x ∧ y )
x ≡ y = ¬ (x ⊕ y)
There is no information leakage in theory if you just take the inverse of a perfectly symmetric function, it has to be perfect in both ways in theory.
What are you thoughts?