The licensing infrastructure in vCenter Server uses a set of terms to refer to different licensing-related objects.
License Key An alphanumeric sequence of 25 characters in groups of five separated every group. The license key encodes details for the product it is associated with, the license expiration date, the license capacity, and other information. The license key is entered in the system to activate the product it is associated with.
Product A set of functionality that you can purchase together as a group. Products are vCenter Server, vSphere, and solutions.
License Edition Enables a specific set of features for the product that the license is associated with. Examples of license editions are vSphere Enterprise, vSphere Standard, vCenter Server Essentials, and so on.
Feature Functionality that is enabled or disabled by a license with a specific edition associated with a product. Examples of features are vSphere DRS, vSphere vMotion, vSphere High Availability, and so on.
NOTE 192 GB is the maximum vRAM entitlement for Essentials and Essentials Plus kits. No additional vRAM entitlement can be added to Essentials or Essentials Plus kits. If more vRAM is required then an upgrade to standard or higher acceleration kit is required.
Solution A product that you can purchase separately from vSphere. Every solution has a licensing model specific for the solution, but can use the licensing infrastructure of vCenter Server for license management and reporting. Examples of solutions are vCenter CapacityIQ, vCenter Site Recovery Manager, vCenter Chargeback, and so on.
Asset Any licensable object in vSphere. The license administrator in vSphere can assign one license key to one or multiple assets of the same type if the key has enough capacity. Assets are vCenter Server systems, ESXi hosts, and solutions.
License Key Capacity Amount of units that you can assign to assets. The units of a license key capacity can be of different types depending on the product that the license key is associated with. For example, a license key for vCenter Server determines the number of vCenter Server instances that you can license with the key.
License Use Number of units that an asset uses from the capacity of a license key. For example, if you assign a per-virtual-machine license key to vCenter Site Recovery Manager, the license use for Site Recovery Manager is the number of protected virtual machines.