First Look: Windows Server 2008

Rethinking server roles

Microsoft wants administrators of Windows Server 2008 editions (it will ship in the usual flavors of Standard, Enterprise, Data Center and Itanium-specific code) to think of the server as playing certain roles. Server roles are aggregated objects that suit commonly thought-of services, such as print services, file sharing, DNS, DHCP, Active Directory Domain Controller and IIS-based Web services. Microsoft has defined 18 roles in all.

There's even a minimalist installation called Windows Server Core that can run various server roles (such as DNS, DHCP, Active Directory components) but not applications (like SQL Server or IIS dynamic pages). It's otherwise a scripted host system for headless operations. There's no GUI front end to a Windows Server Core box, but it is managed by a command line interface (CLI), scripts, remotely via System Manager or other management applications that support Windows Management Instrumentation (WMI), or by Remote Terminal Services. It's also a potential resource-slimmed substrate for Hyper-V and virtualization architectures.

The services running on any role-based server are partitioned and enabled through Server Manager, Microsoft's renamed, revamped administrative application -- either through its GUI or CLI front end. It's a vast improvement over the 'Configure Your Server' routines found in Windows 2000 and 2003 editions. Once successfully enabled, the roles can be easily changed. The CLI version allows scripted initial or remote role changes for administrators. Server Manager adds an important improvement over prior management applications: it checks application dependencies thoroughly before it effects installation, changes, deletions or other alterations.

Capable Security

We got a nearly immediate taste of higher security these server roles allow when we installed Windows 2008 Server -- strong administrative passwords are now required as the default.

Active Directory Certificate Services have been redesigned, and now join with Group Policy settings to allow easier certificate enrollment, discovery and storage. The public-key infrastructure that was formerly very difficult to establish, monitor and maintain in Windows 2003 Server editions has improved dramatically as choices for certificate management (including storage, issuance and certificate vetting) are wider than ever before.

A side benefit is that IPSec encryption can be used with a number of previously unavailable cryptography methods, such as elliptic-curve Diffie-Hellman or Advanced Encryption Standard choices, allowing a simple but heretofore difficult security hole to be patched: Windows 2008 can provide comprehensive network encryption services, network-wide.

In addition to Server Manager, server-based Windows Firewall MMC snap-in helped us configure and manage host based security more easily. Windows Firewall on Windows 2008 Server-based networks can be now controlled by system enforced Group Policy Objects (GPO) within Active Directory. The ability to enforce Windows Firewall settings within an Active Directory domain provides a hierarchically enforced mechanism that thwarts branch office or subsidiary server settings made by local administrators. It's an iron-fist policy that has teeth, and we really like that.

The GPOs can now define server IP address admittance, allowing servers to simply ignore traffic from all but specific addresses, reducing their attack surface dramatically. Policies for specific routes are inherited by all clients and servers admitted to the Active Directory-controlled network, which then allows possible intruder activity to be more readily discerned from the noise of general traffic.

However, this admittance control alone doesn't reduce the effects of TCP SYN DOS attacks, but other TCP/IP settings shipping with only Windows Server 2008 can be used to reduce the effect of TCP connection-focused distributed denial-of-service (DoS) attacks.