<P> Upgrades from Windows Server 2008 and Windows Server 2008 R2 are supported, although upgrades from prior releases are not . </P> <P> Windows Server 2012 has four editions: Foundation, Essentials, Standard and Datacenter . </P> <Table> <Tr> <Th> Specifications </Th> <Th> Foundation </Th> <Th> Essentials </Th> <Th> Standard </Th> <Th> Datacenter </Th> </Tr> <Tr> <Th> Distribution </Th> <Td> OEM only </Td> <Td> Retail, volume licensing, OEM </Td> <Td> Retail, volume licensing, OEM </Td> <Td> Volume licensing and OEM </Td> </Tr> <Tr> <Th> Licensing model </Th> <Td> Per server </Td> <Td> Per server </Td> <Td> Per CPU pair + CAL </Td> <Td> Per CPU pair + CAL </Td> </Tr> <Tr> <Th> Processor chip limit </Th> <Td> </Td> <Td> </Td> <Td> 64 </Td> <Td> 64 </Td> </Tr> <Tr> <Th> Memory limit </Th> <Td> 32 GB </Td> <Td> 64 GB </Td> <Td> 4 TB </Td> <Td> 4 TB </Td> </Tr> <Tr> <Th> User limit </Th> <Td> 15 </Td> <Td> 25 </Td> <Td> Unlimited </Td> <Td> Unlimited </Td> </Tr> <Tr> <Th> File sharing limits </Th> <Td> 1 standalone DFS root </Td> <Td> 1 standalone DFS root </Td> <Td> Unlimited </Td> <Td> Unlimited </Td> </Tr> <Tr> <Th> Network Policy and Access Services limits </Th> <Td> 50 RRAS connections and 10 IAS connections </Td> <Td> 250 RRAS connections, 50 IAS connections, and 2 IAS Server Groups </Td> <Td> Unlimited </Td> <Td> Unlimited </Td> </Tr> <Tr> <Th> Remote Desktop Services limits </Th> <Td> 50 Remote Desktop Services connections </Td> <Td> Gateway only </Td> <Td> Unlimited </Td> <Td> Unlimited </Td> </Tr> <Tr> <Th> Virtualization rights </Th> <Td> N / A </Td> <Td> Either in 1 VM or 1 physical server, but not both at once </Td> <Td> 2 VMs </Td> <Td> Unlimited </Td> </Tr> <Tr> <Th> Active Directory Lightweight Directory Services </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Active Directory Federation Services </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Active Directory Rights Management Services </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Application server role </Th> <Td> Yes </Td> <Td> Partial </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> DHCP role </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> DNS server role </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Fax server role </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Print and document services </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Server Manager </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> UDDI services </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Web services (Internet Information Services) </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Windows Deployment Services </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Windows Powershell </Th> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Active Directory Domain Services </Th> <Td> Must be root of forest and domain </Td> <Td> Yes </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Active Directory Certificate Services </Th> <Td> Certificate Authorities only </Td> <Td> Certificate Authorities only </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Hyper - V </Th> <Td> No </Td> <Td> No </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Server Core mode </Th> <Td> No </Td> <Td> No </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> <Tr> <Th> Windows Server Update Services </Th> <Td> No </Td> <Td> No </Td> <Td> Yes </Td> <Td> Yes </Td> </Tr> </Table> <Tr> <Th> Specifications </Th> <Th> Foundation </Th> <Th> Essentials </Th> <Th> Standard </Th> <Th> Datacenter </Th> </Tr>

Comparison of standard and datacenter editions of windows server 2012
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