We have previously examined the Enrollment for Core Infrastructure (ECI) program, a relatively recent “add-on” under the Microsoft Enterprise Agreement. ECI provides for volume licensing of Core Infrastructure Server Suite (CIS Suite), a server operating systems and management software bundle. ECI offers three flavors of the CIS on a per-processor basis: Standard, Enterprise, and Datacenter. The main benefit of the ECI aside from its potential costs savings is the simplification of server licensing for virtualization.

Under the Standard edition, which is the only version that can be installed on a single physical processor server, the customer can run one instance of a virtual Operating System Environment (OSE) for each physical OSE installed. With the CIS Suite Enterprise edition, customers get two virtual OSEs for every physical OSE, though you can only run one instance per virtual OSE. This means that administrators must pay attention to the virtualization deployments to ensure compliance with the license. The Datacenter edition comes with no such restrictions—there is no limit to the number or configuration of virtual OSEs on the server, often vastly reducing compliance-related burdens for the OSEs and management software installed on the server.

It is important to note, however, that with the CIS Suites, customers still must ensure that any additional licensing requirements are met. For instance, any necessary external connectors, CALs, or Management Licenses needed to manage other servers must be purchased under a different licensing model (CIS Suites are the only products available under the ECI). Also, customers may not run either the Enterprise or Datacenter versions of CIS on servers with less than two processors and further may not unbundle the components to run on different physical servers. However, unlike the standard EA Qualified Desktop or User deployment, you can mix and match your CIS Suites under ECI so long as you meet the minimum, 50-server requirement.