TBM Towers

Towers and Sub Towers represent the technology view of spend in the TBM model.

Use Towers to classify which technology function or service area is supported by the spend after costs have been mapped through Cost Pools. Towers help IT, Finance, FinOps, and business leaders understand how technology spend supports the operating environment.

Towers move reporting beyond what was purchased and into what technology capability the spend enables.

What Towers help you do

Use Towers to:

• Analyze spend by technology function

• Understand cost drivers across infrastructure, applications, workplace, security, and IT management

• Compare technology service areas across periods

• Support Cost Transparency reporting and drilldowns

• Validate allocation outcomes after Cost Pool mapping

• Prepare spend for solution and consumer reporting

• Support showback, chargeback, planning, forecasting, and analytics

Towers provide the IT operating lens of the TBM model.

How Towers fit the TBM model

Towers sit after Cost Pools in the TBM cost flow.

They answer the question: Which technology function does this spend support?

The typical flow is:

1. Financial data is mapped into Cost Pools and Sub Cost Pools

2. Cost Pool spend is allocated into Towers and Sub Towers

3. Tower spend is connected to Solutions and Consumers where the model supports it

4. The results become available in Cost Transparency, Analytics, showback, chargeback, and planning workflows

This structure helps teams explain technology spend through operational service areas.

Tower structure

Towers are organized into two levels.

Sub Towers provide more precise reporting while preserving a consistent technology view for leadership and stakeholder analysis.

Core TBM Towers

Yarken supports Tower and Sub Tower structures that align technology spend to functional service areas.

Common Towers include:

The exact structure can vary by environment and taxonomy configuration.

Data Center

Use Data Center for facilities and physical environments that house technology equipment.

Examples include:

• Data center space

• Power consumption

• Racks and cabling

• Computer rooms and IT closets

• Co-location facilities where applicable

This Tower helps teams separate facility-related technology cost from compute, storage, and network costs.

Compute

Use Compute for physical and virtual processing resources.

Examples include:

• Physical servers

• Virtual servers

• Windows and Linux servers

• Unix platforms

• Mainframe platforms

• Appliances with compute, storage, and network capabilities

• High-performance computing environments

Compute spend is commonly reviewed alongside hosting type, cloud consumption, applications, and infrastructure strategy.

Storage

Use Storage for centralized storage and data retention services.

Examples include:

• SAN and NAS storage

• Backup and recovery

• Archive storage

• Mainframe storage

• Disaster recovery-related storage

Storage analysis helps teams understand capacity, resilience, backup, and archive cost drivers.

Network

Use Network for communication infrastructure and connectivity.

Examples include:

• Data center network equipment

• End user and office network connectivity

• Voice equipment and services

• Data circuits and access services

• PBX, VoIP, voicemail, and related voice services

Network reporting helps teams review connectivity cost, service reliability, and network ownership.

Platform

Use Platform for technology platforms that support applications and data services.

Examples include:

• Databases

• Middleware

• Integration services

• Container management

• Data platforms

• Application and system integration resources

Platform reporting helps teams understand the cost of shared technology foundations used by applications and services.

End User

Use End User for services and assets used directly by employees and end users.

Examples include:

• Desktops and laptops

• Mobile devices

• Productivity software

• Printers

• Audio and video conferencing equipment

• Service desk and local support

End User reporting supports workplace cost analysis, device strategy, license review, and user support planning.

Application

Use Application for application-related development, operations, support, and licensing.

Examples include:

• Application development projects

• Application operations and support

• Minor enhancements and fixes

• Off-the-shelf application licensing, maintenance, and support

Application Tower analysis helps connect software and service delivery costs to application portfolios and solution reporting.

Security, Delivery, and IT Management

These Towers help separate governance, operations, and management activities from direct infrastructure or application delivery.

Use Security & Compliance for security operations, compliance, vulnerability management, and disaster recovery controls.

Use Delivery for service delivery, monitoring, incident, problem, change, and IT operations activities.

Use IT Management for IT leadership, strategy, architecture, planning, budgeting, and vendor management.

These categories help leadership understand the cost of running, governing, and managing the technology organization.

Relationship with Cost Pools

Cost Pools explain the financial type of spend.

Towers explain the technology function supported by that spend.

For example:

• Hardware spend may support Compute, Storage, Network, End User, or Data Center Towers

• Software spend may support Platform, Application, Security, or End User Towers

• External labor may support Delivery, Application, IT Management, or Security Towers

• Facilities and power spend may support the Data Center Tower

This relationship gives teams both a finance view and a technology operating view.

Relationship with Solutions and Consumers

Towers help prepare spend for business-facing reporting.

Once spend is allocated through Towers, it can be connected to Solutions and then to Consumers where the model supports it.

This helps teams move from technology function to service delivery and business accountability.

Relationship with Cost Transparency and Cost Explorer

Towers appear in Cost Transparency dashboards and drilldown reports.

Use Tower reporting to identify high-cost service areas, compare spend across technology functions, and investigate variance.

Use Cost Explorer to validate how Cost Pool spend flows into Towers and how Tower spend connects to downstream Solutions and Consumers.

Recommended practices

Use these practices when working with Towers:

• Validate Cost Pool mapping before reviewing Tower results

• Use the most specific Sub Tower available where detail is needed

• Keep Tower mapping consistent across reporting periods

• Avoid using broad categories when a better Tower is available

• Review unmapped or partially mapped Tower spend regularly

• Coordinate Tower mapping decisions with IT service owners and TBM owners

• Use Cost Explorer to validate allocation outcomes

• Use Tower reports to support operational and executive reviews

Good Tower mapping improves the accuracy of technology service reporting.

Common use cases

Towers are commonly used for:

• Technology function cost analysis

• Infrastructure and operations reporting

• Application and platform cost review

• End user and workplace cost analysis

• Security and compliance cost visibility

• Cost Transparency drilldowns

• Allocation review and model validation

• Planning, forecasting, showback, and chargeback workflows

Troubleshooting Tower results

If Tower results do not look correct, check:

• Whether Cost Pool mapping is complete

• Whether Tower allocation rules are configured correctly

• Whether spend has been mapped to the correct Tower and Sub Tower

• Whether large balances remain unmapped or partially allocated

• Whether source spend exists for the selected period

• Whether downstream Solution reporting depends on incomplete Tower allocation

If totals still do not match expectations, use Cost Explorer to trace the spend path from Cost Pools into Towers.

Next step

• TBM Solutions

Related content

• Technology Business Management

• TBM Cost Pools

• TBM Taxonomy

• Tower Spend

• Cost Explorer

• Cost Transparency Overview