Relate PSR and CSDM for Telecom domain

surya123 · ‎08-10-2026

Hi,

I am working on a Telecom PSR model in ServiceNow and trying to understand how the PSR model should be aligned with CSDM and Install Base Items.

I would appreciate insights from anyone who has implemented PSR in the telecom domain.

My questions are:

CFSS/RFSS and Install Base Items
How are CFSS and RFSS typically connected to Install Base Items so that the PSR model is correctly aligned with the CSDM framework?
Is there an OOTB relationship/pattern for this, or is additional configuration required?
CFSS → Business Service / Business Service Offering
In CSDM, how should a CFSS be represented in relation to a Business Service (BS) and Business Service Offering (BSO)?
Should the CFSS and Business Service represent the same service concept/name, or should they remain separate objects with a relationship between them?
RFSS → Technical Service / Technical Service Offering
Similarly, how should an RFSS map to a Technical Service (TS) and Technical Service Offering (TSO)?
Should the RFSS and Technical Service be the same concept/name, or are they separate PSR and CSDM objects that should be related?
Product vs Product Offering vs Product Specification/Model
I noticed that Product Offering has reference fields for Product Specification and Product Model/Product.
How should these relationships be understood in the PSR model?
Specifically, is the relationship Product → Product Offering one-to-many, and what is the role of Product Specification versus Product Model in this relationship?
End-to-end Telecom PSR + CSDM data model
Has anyone implemented a complete end-to-end Telecom PSR model aligned with CSDM?
If so, I would particularly like to understand the relationships between:
Product->Product Offering->Product Specification->CFSS->RFSS>Resource Specification->Install Base Item / CI-
and how these connect into:
Business Service->Business Service Offering->Mapped Application Service->Technical Service->Technical Service Offering
Service Mapping / Dependency View: Once the PSR/Install Base Item is connected to the CSDM service model, how is the relationship to the Mapped Application Service normally established? How does this then allow events/alerts on the underlying CIs to be viewed in the service dependency map?

surya123 · ‎08-27-2026

@ShashankInamdar can you please help here. I want to understand the logical flow aswell- Is the below correct?

I can associate Install base item to Service specification and that to mapped app services. But where can I actually have the instantiated CFS? Is it same as Map app service? But isnt it that Map app service is the tech layer and cfs should be somewhat Business services? CFSS should be connected to RFSS? And each RFS should be created as technical service and then connected to Map app services? can you please explain the sequence of flow and how I can achieve csdm model with PSR modelling aswell.

PRODUCT SPECIFICATION

(sn_prd_pm_product_specification)

PRODUCT OFFERING

(sn_prd_pm_product_offering)

PRODUCT INVENTORY / SOLD PRODUCT

(sn_prd_invt_product_inventory)

INSTALL BASE ITEM

(Customer Product Instance)

CFS Specification

(sn_prd_pm_service_specification)

Type = Customer Facing

RFS Specification

(sn_prd_pm_service_specification)

Type = Resource Facing

RESOURCE SPECIFICATION

(sn_prd_pm_resource_specification)

CI / RESOURCE INSTANCE - this is the CI;s in the TNI classes. we can directly connect ci to app service and not connect to resource specification?

s_b1 · 2 weeks ago

These are excellent design questions. Kudos for asking them.

There isn’t a single place or document that covers all of them. However, I’ve tried to put together what I think will be a good starting guide for you.

The basic point to understand is that there are 3 different layers.

These three layers, connected by CSDM as the common data model:

Design (catalog): SOM / Product Catalog defines what can be sold and how it’s built: Product Offering → Product Spec → CFSS → RFSS → Resource Spec.
Commercial (order): SOM captures what was sold: quote → order → product inventory / sold product.
Service (consumption): CSM supports what the customer uses and needs help with: install base items, cases, and proactive service.

CSDM is the spine that ties these to operational services (Business Service, BSO, Technology Management Service and Offering) and to the CIs underneath, so impact and ownership flow end to end.”

The principle that answers most of this is to connect the PSR catalog and CSDM, not merge them. CFSS, RFSS and Resource Spec are design-time templates (TMF SID). BS/BSO and Technology Management Service/TMO are operational CSDM records. Sold Product, Install Base Items and CIs are the run-time bridge between the two.

IBI: The IBI Specification field drives the IBI hierarchy at fulfilment (product → CFSS → RFSS → resource). That part is OOTB. The CI class per level and the CI relationships between them are yours to design.
CFSS → BS/BSO: Keep them separate and related. The BS is the service family and the BSO is the tier or commitment. Sold Product references the Service Offering once CSM is integrated with SPM. A CFSS → BSO reference is custom.
RFSS → TMS/TMO: Same approach. Resource-facing service instances and resource CIs become TMO members. An RFSS → TMO reference is custom.
Product objects: Product Specification → Product Offering is 1:many. The Product Model has a single specification, and that is what keeps Sold Product and IBI aligned with CSDM.
End-to-end: I haven’t found a public reference implementation of the full chain. The SASE Custom Solution Bundle covers the catalog side .
Alerts: Link the CFS-level IBI’s Configuration Item to a Service Instance. Build the service map from CFS → RFS → resource CIs (top-down mapping is rare for network services). Event Management then rolls impact up, and Proactive Customer Service Operations surfaces the affected IBIs. Without CI relationships between those levels, alerts never reach the customer.

Worth verifying the CFS/RFS inventory table names on your release, as they vary between TMT versions.

Here are some artefacts to guide you. Some of them may be out of date, so check the best practices library and community for latest updates.

https://www.servicenow.com/community/csm-articles/aligning-sold-products-and-install-base-items-with...
https://www.servicenow.com/docs/r/telecom-media-technology/somt-map-sid-catalog.html

https://www.servicenow.com/docs/r/order-management/order-mgt-product-catalog.html