  Recently Xia and Song [Phys. Lett. A (In press)] have proposed a controlled
quantum secure direct communication (CQSDC) protocol. They claimed that in
their protocol only with the help of the controller Charlie, the receiver Alice
can successfully extract the secret message from the sender Bob. In this
letter, first we will show that within their protocol the controller Charlie's
role can be excluded due to their unreasonable design. We then revise the
Xia-Song CQSDC protocol such that its original advantages are retained and the
CQSDC can be really realized.

Quantum Physics