Hi Ambar,
Configuration Item is a concept used by ITIL and more typical to IT industry than to telecommunications. In ITIL CIs are maintained in a CMDB.
This concept is not used in TM Forum. If you are looking for an equivalent you will see that TM Forum uses a more fine grained model with Services, Resources and Places. On top of that event TroubleTickets, ChangeRequests, WorkOrders and other bussiness interactions are classified as CI.
In the TM Forum each of the above entities have their own OpenAPI.
To understand the Information Model behind the OpenAPI, I suggest to start with a document called "GB922 Primer".
TMF639 Resource Inventory and TMF638 Service Inventory probably will guide you to the concepts most recognisable for people with an ITIL background.
I hope this helps.
Regards
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Koen Peeters
OryxGateway FZ LLC
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