What is the punctuation mark should be in short version of someone's introduction?

For example, 3 people meets, but 2nd and 3rd don’t know each other. 1st said, "Hi, everyone. Mike, this is John. John, this is Mike."
But if 1st person desided to shortening introduction, removing ‘this is’, what would be punctuation in "Hi, everyone. Mike John. John Mike." Dashes? Commas? Nothing? Or…?