How Secure Are Two-Way Ping-Pong and LM05 QKD Protocols under a Man-in-the-Middle Attack?

We consider a man-in-the-middle attack on two-way quantum key distribution ping-pong and LM05 protocols in which an eavesdropper copies all messages the message mode, while being undetectable mode. Under there is therefore no disturbance mode mutual information between sender receiver always constant equal to one copied by are genuine. An can only be detected control but level of detection at protocol should aborted not defined. examine steps evaluate its security find that redesigned. also compare it with one-way asymmetric BB84-like basis serves as other does have