Comment by lisper
> That's a little sloppy
Yes, that is exactly my point. The only way you can make it non-sloppy is to define "delivery" as being something that happens exclusively upstream of deduping.
> That's a little sloppy
Yes, that is exactly my point. The only way you can make it non-sloppy is to define "delivery" as being something that happens exclusively upstream of deduping.
No, I'm saying its "sloppy" as a definition because while it addresses the distinction you ask about it, it doesn't fully cover what distinguishes exactly-once from at-most-once.
> The only way you can make it non-sloppy is to define "delivery" as being something that happens exclusively upstream of deduping.
"Deduping" can happen in many places. If it happens anywhere before the destination system end of the unreliable connection it is part of delivery (but also can't get you to exactly-once delivery). If it happens on the destination side of the unreliable communication channel, then yes, it's not part of the delivery guarantee, it is how you get exactly-once processing from at-least-once delivery. This has been well-known for a very long time. (I don't think it was new when I first encountered it in 1999.)