You're right in saying that, for example, exactly once delivery is a symptom of a business requirement. I do agree, but even something like message de-duplication has issues with scaling in a genuinely distributed system. Admittedly, whether you choose to look at that as part of messaging (a term which I admit to possibly over-broadening sometimes, as I tend to look on it as more of an approach than a technology) is open to debate, but I do get where you're coming from much better now.
On the second point, I wouldn't describe my scenario as a distributed transaction - there's also very possibly no single server on which to do a classic database transaction - as soon as you do there's a scalability barrier. Anyway - it's more a difference of scenarios I think, and I'd agree that in the ones you've described the solutions sit outside of a messaging layer/domain.
Always interesting to hear, thanks for clarifying!
You're right in saying that, for example, exactly once delivery is a symptom of a business requirement. I do agree, but even something like message de-duplication has issues with scaling in a genuinely distributed system. Admittedly, whether you choose to look at that as part of messaging (a term which I admit to possibly over-broadening sometimes, as I tend to look on it as more of an approach than a technology) is open to debate, but I do get where you're coming from much better now.
On the second point, I wouldn't describe my scenario as a distributed transaction - there's also very possibly no single server on which to do a classic database transaction - as soon as you do there's a scalability barrier. Anyway - it's more a difference of scenarios I think, and I'd agree that in the ones you've described the solutions sit outside of a messaging layer/domain.
Always interesting to hear, thanks for clarifying!