Alice has a message, generates a one time pad, encrypts her message and sends it to Bob. Bob generates his own one time pad, encrypts the message again, and sends it back to Alice. Alice then decrypts this message using her one time pad, sends it back to Bob who then decrypts it the last time using his one time pad.
The only problems I see with this technique:
- It is vulnerable to a man in the middle attack.
- It requires sending the message back and forth twice between sender and recipient.
- It doesn't scale well if you want to use it to communicate with multiple people.
- Requires a way of generating cryptographically secure random numbers.
Does this method of encryption have a name?
If we ignore the fact that it's vulnerable to a man in the middle attack, is this method of encryption information-theoretically secure?
Why isn't this method used widely, i.e. which of the above listed problems or other problems makes this method infeasible for production use?