Inventory modelling - Resource Specification versus CI

[Gaurav Tewari]

We need to model CFS, RFS, Resource and its Installed Base Item (IBI). Project is using OMT and CSM along with ITSM. There are 2 options:

1. We can model CFS and RFS in OMT Service Specification and resource as Resource Specification. Further  Resource Specification can be related to Service Specification using OOB relationships. But if we do that then we cannot get the inventory in CI-IBI-Sold Product model.
2. Alternatively we can model the resource as a CI which will be related to Sold Product via the IBI in Installed Products. But in this option modelling the CFS and RFS will be a challenge.

Please suggest on how to model the resource so that I can relate Resource Specification with CI. 

[ShashankInamdar · Accepted solution]

@Gaurav Tewari 

I can rephrase your question as - when should a Resource be modelled as a Resource Spec versus a Configuration Item?

A Resource in the context of P-S-R model, represents a tangile or intangible entity required to deliver a Service and where the Resource solely belongs to the customer such that it's lifecycle is tightly coupled with the customer. If the customer decides to disconnect, the Resource instance is also deactivated.

A CMDB CI is Resource+. By that, I mean the CI can represent a Resource that solely belongs to the customer but it can also represent a shared Resource instance that is common across different customers and serves more than one Service.

Based on this, a Resource can be represented in 3 ways -

[1] Only as a Resource Spec, and the instantiated record are stored in the Product Inventory table.

[2] Only as a CI, which can be linked to the Service Spec via Install Base Item

[3] Both as a Resource and CI

Pattern 2 and 3 are useful in Service Impact Analysis and Assurance use cases.

Based on your needs, you can either follow pattern 2 or 3.

You do not need TNI for this.

You mention, if you model the Resource as a CI then modelling CSF/RFS is a challenge. This I do not understand. Can you elaborate?

[Arunava1]

Hi @ShashankInamdar ,  On the point no [2], I analysed the fulfilment flows given in the base system and I see that, from Service Specs we are creating CIs which are basically Services. Other CI classes(ex. SDWAN Edge) are being created during processing the Resource Order hence associated with the Resource Specs.. Can you confirm if this approach can be taken as a standard ?

Thanks !

Arunava

[ShashankInamdar]

Hi @Arunava1 , yes this is a standard way of modelling this.

[Mahesh_Krishnan]

@Shashank is it in the linkage we created between the Specification Category and Model Category that a CI record gets created? Besides this connection I cannot recall any other place where the OMT and CMDB connect except with the TNI integration. 

[ShashankInamdar]

Hi @Mahesh_Krishnan , the Model Category plays a role in Asset creation not in CI creation. The CI needs to be explicitly created via workflows. The linking of Specifications and CMDB CI's is managed in the Install Base Item table. There is an OOTB action "Create Install Base Item and Installed Product" available with the OM App.

OMT-TNI integration use cases are for Design and Assign. But one does not need TNI to create CI records via OMT and/or to link it with Sold Product/Specs.