Hi Jiri,
Regarding TMF645:
The flat structure in TMF645 is by design and there is no other way.
Nesting implies a containment hierarchy but in the SID:
It's impossible to construct a hierarchy of Sspecs based on the bundle product offering hierarchy.
Because TMF645 qualifies ServiceSpecifications, and no SSpec hierarchy exists, nested SQIs would have no semantic foundation in SID/TMF645.
qualificationItemRelationship is therefore the only valid way to relate items if you need to define dependencies. I hope the TMF645 design team will confirm this.
and about TMF641:
In TMF641, the ServiceOrderItem concept supports nested service order items, which is very convenient for composite (bundle) services made of multiple components.
Are you suggesting that 641 nesting reflects product catalogue-driven hierarchy (bundle product offerings in the product catalogue?).
I don't believe that's possible.
I believe 641's serviceOrderItem is a hierarchy created dynamically by the service decomposition/orchestration layer (e.g., CFS → RFS expansion) to group technical services for lifecycle and orchestration. (this is maybe a case where you can use SSpec collection defined in the Service Catalogue).
Thus, TMF641 nesting and TMF645 flatness are by design and serve different purposes.
The OSS experts will probably give you a better answer!
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Kind regards,
Matthieu Hattab
Digital Sales, Core Commerce Domain Architect
Ex-Lyse Tele, Open to Work
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