Hi Carsten
In the Open API model, a recurring fee is modeled as a ProductPrice (in the inventory), derived from a ProductOfferingPrice (in the catalog).
These are visible in the respective APIs (TMF637 and TMF620).
The existence of such a fee will eventually cause an AppliedCustomerBillingRate (ACBR) to be generated onto the periodic bill (TMF678).
Usage is not the same as recurring - in the case of very fine-grained usages (e.g. telephone calls) - the usage records will be rated and aggregated into ACBR, while coarse-grained usages (e.g. consuming digital content) could be considered in some billing models as individual one-time charges.
You can of course model a usage allowance that gives e.g. 100 SMS messages per billing period, for which a recurring charge of 2 Euro is paid.
Hope it helps
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Jonathan Goldberg
Amdocs Management Limited
Any opinions and statements made by me on this forum are purely personal, and do not necessarily reflect the position of the TM Forum or my employer.
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