Multiple domain names can be hosted on a single computer running Microsoft Internet Information Server (IIS) using virtual servers. There are three ways of hosting virtual servers on IIS.

  • The first is to obtain a unique Internet protocol (IP) address for each domain name assigned to the server.
  • The second is to use Host Headers. Host Headers allow multiple domain names to be hosted on IIS using a single IP address.
  • The third is to assign a unique port number to each virtual server.

Virtual servers can be established for WWW and File Transfer Protocol (FTP) services running on IIS.
FTP sites can use either unique IP addressing or unique port number assignment to host a virtual server. Only WWW sites can use Host Headers in addition to unique IP addressing or unique port number assignment to host virtual servers.

HTTP that led to the World Wide Web (WWW) grew out of a need for a universal protocol to simplify the way users access information on the Internet. A generic, stateless, object-oriented protocol location in the application layer of the Internet protocol stack, HTTP is used for many functions such as name servers and distributed object management systems through an extension of its request methods or commands.

HTTP categorizes data, allowing systems to be built independently of the data transferred.


IIS stores most of its configuration information in a database called the Metabase, which replaces the function of the registry for IIS. The metabase can be accessed using Active Directory Interface (ADSI). ADSI used as an interface for scripting purposes.

Active Directory Service Interface

Active Directory Service Interface (ADSI) is a general interface for administering services in Windows NT. IIS allows an ADSI provider to connect applications to the metabase using the ADSI interface.

Microsoft Management Console

The Microsoft Management Console (MMC) interface allows snap-ins hosted by the MMC to communicate with the IIS metabase.


HTML based administration (HTMLA) communicates with the IIS Metabase over the Internet or Intranet. This structure enables administration of the Web Server even if the website is down.

Windows Scripting Host

The Windows Scripting Host (WSH) serves as a controller of Active X Scripting engines. Just as Microsoft Internet, Explorer does. Because the Scripting host is not a full Internet browser, it has a small memory footprint and therefore is appropriate for performing simple, quick tasks.

The scripting engine does not use the SCRIPT tag as it is employed in HTML. Instead, it relies on the file name extension. This way, the scriptwriter needs to be familiar with the exact programmer's identifier (ProgID) of various script engines. The scripting host maintains a mapping of the script extension to ProgIDs and uses the Windows association model to launch appropriate engine.