One of the biggest challenges in managing a modern CMDB is figuring out where to put what. Is Microsoft Teams a Business Application? Is Kafka part of Infrastructure? Where do I track Intune, and how do I model a DNS service?

The Common Service Data Model (CSDM5) gives us a structured way to think about this. But it only works if we clearly separate baselines, instances, and service instances. Here’s a breakdown that can help you classify things consistently.

Software in CSDM5

Software (including SaaS) baselines can fall into five categories:

  • Business Applications (business-focused):
  • Owned and managed by the business, offered as part of a Business Service.
  • Business Applications (internally-focussed):
  • Shared and Corporate solutions (e.g., HR/HCM, Risk, Finance, Legal) offered as Internal Business Services to employees.
  • Business Applications (technical-focused):
  • IT-focused tools (e.g., Intune, JAMF, GitLab), offered as part of a Technical Management Service.
  • Software Product Models:
  • Products recognized by the enterprise, with deployable versions (packages) that may be provided via Business or Technical Services.
  • Unsupported Solutions:
  • Tools not offered as a Service and therefore not officially registered by the company.

Notes on Software

  • Business-focused applications → the Application Owner manages lifecycle, risks, and interfaces.
  • Middleware (Java, Kafka, MQ, Tomcat, SQL Server, DNS, DHCP) → modeled as Infrastructure, provided via Technical Services.
  • Operating systems & drivers → part of Infrastructure (blueprints), tied to Technical or Business Services.
  • Data/AI sources consumed as a Service → offered as Technical or Business Services.
  • End-user software:
    • (Notepad, Calculator) → part of End-User Computing (Business Service).
    • Bundled tools (Deployable via Company Portal → Software Product Models/Packages offered as Business Services.
    • SaaS apps (Office 365, Google Workspace, Slack, Teams) → Business Applications offered as Business Services.

ServiceNow Tables for Software

Table Purpose Example
Software Model
(cmdb_model_software)
Recognized product baseline Microsoft Visio 2021 Professional
Software Packages
(cmdb_ci_spkg)
Deployable unit Visio_Pro_x64_en-us.msi
Software Instances
(cmdb_ci_software_instance)
Installed Reality Visio 2021 on LAPTOP-1234

Infrastructure in CSDM5

Infrastructure baselines represent the hardware and technical backbone. They can be:

  • Product Models (computers, phones, peripherals, bundles, licenses, consumables) → offered as part of a Business Service.
  • Technical Capabilities (e.g., network routing, virtualization, storage clusters) → offered as part of a Technical Management Service.

Notes on Infrastructure

  • Physical infrastructure with monetary value → tracked as Hardware Assets, including location.
  • Technical infrastructure (cloud, SDN, datacenter services) → modeled as Technical Services.
  • End-user infrastructure (PCs, phones, tablets) → modeled as Business Services, including installed software.

Instances in CSDM5

Baselines define the standard catalog. Instances capture the deployed reality.

Software Instances

  • Stored in: cmdb_ci_software_instance
  • Examples:

    SQL Server 2019 instance running on DB-SRV-45, Visio 2021 installed on LAPTOP-1234

  • Detection: Via SCCM, Intune, MID Servers, cloud connectors.
  • Use: Show the footprint of deployed software, tied back to baselines.

Infrastructure Instances

  • Stored in: cmdb_ci_* tables (e.g., cmdb_ci_computer, cmdb_ci_vm_instance, cmdb_ci_phone).
  • Examples: Laptop-LEN1234 assigned to John Smith VM: AzureVM-WestEurope-Prod01. Cisco Switch SW-AMS-01 in Datacenter A
  • Detection: Discovery tools (ServiceNow Discovery, Intune/JAMF, cloud connectors).
  • Use: Provide the consumption view, linking real devices to baselines and services.

Service Instances in CSDM5

The final layer is the Service Instance, which represents the deployed and running version of a Service that’s consumable by the business or IT.

Types of Service Instances

  1. Business Service Instances

    1. End-user or customer-facing.
    2. Example: Office 365 (Tenant X) for Finance
  2. Technical Service Instances

    1. IT-focused, underpinning business services.
    2. Example: Kafka Messaging Cluster (Production)
  3. Application Service Instances
    1. Running application components.
    2. Example: SAP ERP Production Instance

Relationships

  1. Baselines = standards and governance (e.g., SQL Server 2019 as a Software Model).
  2. Instances = deployed reality (e.g., SQL Server 2019 installed on VM-SQL01).
  3. Service Instances = consumable services (e.g., Finance Database Service powered by SQL Server).

Wrapping Up

CSDM5 provides a disciplined way to classify and manage the complexity of modern IT. By distinguishing between baselines, instances, and service instances, you can:

  • Keep your CMDB clean and accurate
  • Ensure lifecycle and risk management are owned at the right level
  • Make clear connections between technology and business value

The golden rule:
– Baselines = what we recognize
– Instances = what we deploy
– Service Instances = what we consume

Get this right, and your CMDB becomes not just a data repository, but a real foundation for IT governance and business transparency.