[staticassertion]

I don't really know a thing about that sort of network, but if you can assume a reliable network, the machine reading the packets going down shouldn't matter. The sender won't get an "ACK", will know the other machine is at fault and not the network, and can resend.

Given a "perfect network" I think exactly-once-delivery is possible, right?

[mac01021]

What if the sender fails before it can fully process the ACK? When it comes online again it won't know that the last message sent was delivered.

[staticassertion]

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