Web server (IIS) support role service Vs Application Server role
Why do we have Web server (IIS) support role service(under Application Server role)?
There are huge number of applications that are hosted on IIS server i.e. Exchange, SharePoint, CRM, etc. Not every IT professional will be a web developer and aware of different features that are available under IIS. So if there is user who would like to host his application on IIS server and has no idea what features he would need to add under IIS, then he could go ahead and install the Web server (IIS) support role service(under Application Server role). This will solve his all basic requirements for hosting the web applications on IIS server.
Also this is in line with what we had in Win 2003 server. In Windows 2003 server too IIS was installed as a part of Application Server. So it is incorrect to think that the flexibility have been reduced in Windows 2008 server for user to choose between available features.
Actually flexibility has been increased hugely from Windows 2008 server onwards if we consider IIS web server here. We are provided with the flexibility of installing only the features that we require on IIS server. E.g. if we don’t need basic authentication at all on any of our websites, then we have an option of not installing it. An important point to understand here is that installing a feature and enabling it are two separate operations. We can install a feature and still keep it disabled. Due to this separation of installation and configuration operations, we can actually decide what we need to have as an option on our web server.
If we compare authentication scenario with Windows 2003 server, we had all the authentication types(Anonymous, Integrated Windows, Basic) available on IIS manager. So the administrator can choose between them as per the requirement. From Windows 2008 onwards, we have an option of selectively installing the features that we are going to use. So if we know we are not going to use Basic authentication feature on any of our websites, so we can skip it while installation. So the administrator will get only two options, Anonymous and Integrated, to choose from.
As we see Windows 2008 server provides a higher level of flexibility to the user, at the same time, maintaining same experience for users who have migrated from Windows 2003 server without confusing with too many options available.