What are the Major differences between windows server 2003 and windows server 2008?

 The main difference between2003 and2008 is Virtualization, management. 2008 has more inbuilt components and updated third party drivers Microsoft introduces new feature with2k8 that is Hyper-V  Windows Server2008 introduces Hyper-V (V for Virtualization) but only on64bit versions. More and more companies are seeing this as a way of reducing hardware costs by running several 'virtual' servers on one physical machine. If you like this exciting technology, make sure that you buy an edition of Windows Server2008 that includes Hyper-V, then launch the Server Manger, add Roles.

In Windows Server2008, Microsoft is introducing new features and technologies, some of which were not available in Windows Server2003 with Service Pack1 (SP1), that will help to reduce the power consumption of server and client operating systems, minimize environmental byproducts, and increase server efficiency. Microsoft Windows Server2008 has been designed with energy efficiency in mind, to provide customers with ready and convenient access to a number of new power-saving features. It includes updated support for Advanced Configuration and Power Interface (ACPI) processor power management (PPM) features, including support for processor performance states (P-states) and processor idle sleep states on multiprocessor systems. These features simplify power management in Windows Server2008 (WS08) and can be managed easily across servers and clients using Group Policies.

And below the new fetures that added to windows server2008

1.RODC one new domain controller introduced in it

   [Read-only Domain controllers.]2. WDS (windows deployment services) instead of RIS in2003 server3. shadow copy for each and every folders4.boot sequence is changed5.installation is32 bit where as2003 it is16 as well as32 bit, that’s why installation of2008 is faster6.services are known as role in it7. Group policy editor is a separate option in ads

8. group policy prefrances 

- when windows2008 came the main difference with windows2003 was the initiation of virtualization

- we get new windows version which is core version

- services that the server deliver is known as roles and features in windows2008 

- in the domain we got new domain controller type which is read only domain controller

-  windows deployment service WDS instead of RIS

-  shadow copy

- NAP 

- bitlocker for protecting the hard drive

- powershell module for all windows os services you can control them using powershell

- group policy enhancement and get group policy management  as seperate feature

- Advanced Configuration and Power Interface (ACPI)

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