What is a common service data model (CSDM)?

The CSDM provides service reporting and guidelines for service modelling in the ServiceNow Configuration Management Database (CMDB). The model includes guidelines for using the base system tables. It aligns configuration items (CIs) and services with your business strategy.

A reactive approach to digital products and delivery can dominate without an IT focus on standardisation, integration, and application of a common approach. CSDM helps you connect terminology to help make decisions for strategy, planning, developing, troubleshooting, root cause analysis, and executing changes.

CSDM is considered the best practice for CMDB modelling and management—it provides direction on modelling and comes with a standardised set of definitions. It is a connection between business and technical perspectives with mapping and relationships. It provides visibility into application and service data from varying domains, consolidating everything into a single view. This gives your organisation the opportunity to align your IT and company strategies. CMDB with a high-quality CSDM also provides multiple benefits like faster incident resolutions, better security, and better judgment of the impact of change.

The common services data model can act as a blueprint to map your IT services on the ServiceNow platform—it is a CMDB-based framework that outlines where to place data for the other products that are in use. CSDM is also a standard for ServiceNow products that use CMDB. If you follow the CSDM framework, you’ll ensure that the data in the application maps to the correct CMDB table which minimises duplicate, incorrect, and out-of-date data.

Products from ServiceNow that use the CMDB deliver better benefits faster when using the CSDM. Adopting it will ensure that:

• You will be able to take better advantage of ServiceNow products
• Upgrading will be an easier, more straightforward process
  
• ServiceNow products will work better in conjunction with common definitions across the product portfolio

Use of CSDM will also provide transparent reporting and service costing, in addition to reduced overhead from services maintenance.

CSDM is a powerful framework for CMDB data modelling and management, providing essential guidance and visibility. But it does have its limitations. Getting the most out of CSDM means recognising what it can, and can’t do for your business. Here are several things that CSDM is not:

• A SKU or product to be purchased
• One-size-fits-all guide to define application or business services
• An automated fix for models in prior implementations
• Code to be installed
• Implementation guide for EM, ITSM, APM, and SPM
• A set of reports

ServiceNow provides all CSDM objectives and the CMDB tables as a part of the out-of-the-box CMDB product, regardless of licensing.

You can use the CMDB builder to generate reports that show CMDB items and their relationships. Most of CSDM follows CMDB, which includes:

• Business capability
• Information object
• Service
• Business application
• Application service
• Service offering

While CSDM provides certain clear advantages, some organisations find themselves poorly prepared to get the most out of the common services data model. When this happens, the issue can usually be traced back to one or more of the following problems:

• Poor architectural alignment with CMDB.
  
• Lack of IT ILSM principles.
• No services that are formally defined.
• Segmented data ownership and limited stakeholder collaboration can lead to silos.
• Prior customisation of the CMDB data, like classifying CIs and how to relate them to organisation products, services, and capabilities, that cannot be maintained.

It isn’t advisable to implement each CSDM element all at once. Instead, approach CSDM in stages, and don’t feel like you have to hit every stage for every application or service. ServiceNow defines these stages as Foundation, Crawl, Walk, Run, and Fly. Each stage is explained below:

• Foundation: Ensure you have the foundational information that is needed to generate accurate reports.
• Crawl: Shift your focus to application tables to construct the minimum information needed for incident, change, and problem management.
• Walk: Address management and support of deployed infrastructure.
• Run: Incorporate business services in order to understand the impact that the technology will have on your business.
• Fly: Construct the remaining aspects of CSDM in order to tie the technology and business services to business capabilities.