Hi Caui,
This seems to be a very interesting problem statement. Here's my take on it -
In usual scenarios when there are 2 or more OCS platforms involved, the segregation of subscribers is such that there aren't any use-cases that involve balance sharing (especially when parent and child belong to the same account or business group or a tenancy in general). BSS may still have subscribers across multiple OCS platforms which are a part of the same CUG/Community group, but the subscribers will still be using their own balances/tariffs for making calls at preferential rates.
In your case though, the only viable solution that I can think of is a real-time balance sync between the 2 OCS platforms. As soon as the order for a balance sharing package is successfully provisioned on both the OCS platforms, full data balance should be provisioned on both the platforms. Whenever there is a reservation/credit/debit request on either platform, an API should be triggered from the source OCS (where the request was generated) to the destination OCS for balance sync.
This solution should work fine if both the OCS platforms are supposed to be master OCS.
NOTE: This solution is proposed under the assumption that such scenarios exists only for a few cases and have a scenario identifier so that APIs are triggered only for these subscribers/package combination.
In-case your OCSs are in master-slave mode for balance management, then the APIs will only be triggered from the master platform to keep the slave in sync for balance query, notifications, etc. purposes.
Do connect with me if you have specific questions on the solution.
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Shashank Singh
Cerillion Technologies Limited
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