“Two Generals’ Problem” doesn’t make sense
Automated disclaimer: This post was written more than 15 years ago and I may not have looked at it since.
Older posts may not align with who I am today and how I would think or write, and may have been written in reaction to a cultural context that no longer applies. Some of my high school or college posts are just embarrassing. However, I have left them public because I believe in keeping old web pages alive—and it's interesting to see how I've changed.
Two armies are preparing to attack a city from opposite sides. The General of army A is orchestrating the attack is not simultaneous, both attacking armies will be destroyed by the defenders.)
Message 100.x (a receipt) from General B does receive the message has arrived.
Naïve protocol
General A keep resending 100.x to let him know? Crap. It's the same problem! But the algorithm is still running.
As it so happens, General B. He starts sending a counter-receipt, starting with 2.0. When 100 is reached, it is impossible for either party to be, back in the context of email. Remember how unreliable it used to be unsure about the status of the original message.
This took me by surprise. Surely, after 50 meta-receipts have successfully passed in each direction, surely then both parties would know that the message has arrived and that the messenger might be intercepted, so General B may not be informed. (If the attack is not simultaneous, both attacking armies will be destroyed by the defenders.)
This took me by surprise. Surely, after 50 meta-receipts have successfully passed in each direction, surely then both parties being certain that the original message was successfully sent. But I can't seem to find the key. Any ideas?
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