A major problem with using ICMP is that you'll "stand out like a turd in a punch bowl!" (apologies to the movie Up the Academy). ICMP is used for a limited num

A major problem with using ICMP is that you'll "stand out like a turd in a punch bowl!" (apologies to the movie Up the Academy). ICMP is used for a limited number of very specific things. If you appropriate it for more general use, your traffic will stand out. Look at me! Look at me! Look at me! If you're using crypto, I think rule #1 should be to blend in, to not call extra attention to yourself. I'd rather start my communication by sending a TCP packet to port 443. Just like billions of TCP sessions start every day. That doesn't help you if someone is specifically targeting you, but it might keep you from being noticed initially.