In a Letter, Cabello proposed a quantum key distribution (QKD) Protocol which attended to Holevo limit. In this comment, we show that Eve could use a simple plan to distinguish among quantum keys, without being detected by Alice and Bob. In following
, we show that our approach is not restricted to Cabello Protocol. With attention to our Eavesdropping approach, it seems that Mors arguments for no-cloning principal for orthogonal states is not general enough to avoid eavesdropping.
