My opinion is that if the OP thought that MAC addresses are part of HTTP or called a key exchange protocol an encryption protocol then there must be other people thinking the same, and the correct way to handle this is with comments and answers.
Next time someone finds the question on Google and clicks on it, they'd see that they had a misconception and reading the answers would rectify the situation.
Editing out the misconception, however, teaches the OP nothing. Even worse, it makes it harder for the answerers to truly answer the question. Anything they say might sound confusing to the OP because the initial misconception hasn't been cleared.