How do you realistically calculate TCO or ROI?
People often ask me - do I start with CAPEX or OPEX. The real answer lies within both. Depending on the type of virtualization being implemented for clients you will want to look at the entire lifecycle of the client, application and overall business directives. Remember - that sometimes TCO/ROI is not enough to build a case. This particularly rings true when for example the implementation would have a significant impact on end users ability to perform their job function (Road Warriors, Doctors, Teachers) and their level of connectivity.
Watch Out for Shifting Costs
Virtual Desktops and Applications do have a significant value in certain situations to aid with compliance, reduce application lifecycle costs, and eliminate down time. However there are additional costs that are added that must be considered when building the case to determine if a particular solution or architecture is right for your business.
Each vendor will provide a nice TCO or ROI calculator based on what is "known" today for a typical desktop deployment. However, virtualization of Desktops and/or Applications is anything but typical. It adds additional overhead and complexity that must be added to the calculations such as:
- Reduces Systems Management Ability to Diff (Byte level) updates of applications - increases application data load on networks. This varies per Virtual Application and Systems Management Vendor - needs to be included in your selection test.
- Increases Storage Requirements both in the data center and on the endpoint - this requires additional hard drive/NAS/SAN, etc and computing processing power. For example, prior to Application or Client Virtualization the user typically only had a single copy of the OS or Application on the endpoint. Now they can have multiple copies of the OS, different versions of the same application, and/or programming framework (.Net or JVM). This in turn will also increase storage requirements in the Data Center for storing those multiple copies & impact on network for download, patch and update.
- Increases Management Overhead in other areas - while Virtualization decreases some of the areas of management overhead (Packaging/repackaging) and Test - it does increase the complexity of the overall management overhead. Why? Because prior you had only a single application to patch, update, inventory and manage on a single OS. Now there are multiple OS for single users and multiple apps. Each application will need the same level of care for Patch, Update, Inventory and Management in order to ensure compliance with regulatory, business, and security directives. Part of the ROI should be calculating what the maximum number of applications and/or OS you will support in your client environment and what the costs (with new virtualization factors) will really be.
- Increases Operational Expenses in Other Areas: Before the line between server and desktop was very clear and well drawn with the exception of Citrix Presentation Server (Now XenApp). With the introduction of Desktop Virtualization - many companies are coming to realize that they will need more seasoned experts in the troubleshooting cycle to assist the help desk (solution centers). These individuals have to be Virtual Host experts and be able to determine what server originated what version of what applications and OS to troubleshoot individual issues, audit application access, and understand total impact. Network, Database, Server Virtualization Experts etc will all need to be part of level 2 support (not just escalations any more) and/or Service Desk will need more of these experts. This in turn will drive up Operational Costs.
- Impact to End User Productivity: Depending on the application this one can have mixed results. It is critical to understand who the target users are and what the overall impact this type of technology will have on their job function prior to deciding to virtualize their desktops or applications. For example, their is a big push in Healthcare to provide Clinical Desktops for Physicians, Nurses, and RTs as either virtual desktops or applications. This has had mixed success depending on the implementation and stability of technology. For high bandwidth, high throughput scenarios - it typically works great until the network or electricity is down and/or the Physician tries to access the application remotely from a clinic or home office that has low bandwidth. There needs to be back up procedures and access built into the equation for critical applications as part of the overall DR plan for each user. AND the costs of down time needs to be calculated not just from an hourly dollar amount but overall business impact (liability, customer care, and employee satisfaction). Don't forget - it was the Users not IT that killed the Vista deployments due to overall impact on their job performance...