VMware vCenter Server 6 Standard for vSphere 6 (Per Instance)
VMware vCenter Server 6 Foundation for vSphere up to 4 hosts (Per Instance)
VMware vSphere 6 Enterprise Plus for 1 processor
VMware vSphere 6 Standard for 1 processor
VMware vSphere 6 Essentials Plus Kit for 3 hosts (Max 2 processors per host)
VMware vSphere 6 Essentials Kit for 3 hosts (Max 2 processors per host)