A World Wide Web (WWW) Server is normally a single machine dedicated to processing HTTP requests for a single WWW site. Simply put, one WWW site per machine. Since the computing resources for processing httpd requests is low for most WWW sites, the majority of the computing resources are left unused. A virtual WWW site simple allows more than one WWW site to share a single processor. Instead of having www.domain1.com and www.domain2.com requiring two physical computing devices, www.domain1.com and www.domain2.com can be located on a single computing device and share common resources.
Normally small computing facilities, and small businesses do not have the resources to maintain a dedicated web server and a dedicated Internet connection. These cost can easily start off at $10K for setup, and $500-2500 monthly to maintain. Small computing facilities, and small businesses are now able to "rent" WWW space from a Virtual WWW providers. The customer can then maintain the WWW "pages" using a local telnet and/or FTP connection.
WWW providers such as InfoCom Networks http://www.infocom.net/ provide WWW space as low as $75 per month. A few Virtual Sites might clear up the mystery. So the cost of setting up a WWW site is significantly lower than that of setting up a dedicated server and connection. The Virtual Site has a major advantage over other WWW addressing schemes such as "www.yourprovider.com/~businessname". The Virtual WWW server inherently contains the ability to move to a new location or setup a dedicated WWW server without changing addresses. Changing WWW URL's can result in a major loss of traffic to your site, and lots of business literature updates.
With most web sites, www.domain1.com and www.domain2.com both resolve to separate IP's. In order to accept multiple request from a single host, the virtual host must be able to answer request for both sites. The method used to solve this problem is called IP aliasing. IP aliasing allows a single host to accept request for multiple IP's. The virtual Web server must have the ability to alias IP's .:: ml007.k12.sd.us ::. .:: zenwriting.net ::. .:: med.jax.ufl.edu ::. [Issues with Machine learning]
IP aliasing is just one part of the virtual solution. The Domain Name System (DNS) also must be configured to resolve both www.domain1.com and www.domain2.com. If domain1.com and domain2.com are new domains, then both must be registered with Internic. Currently, Internic is charging $50 a year to maintain your domain. .:: podcasts.apple.com ::.
Most virtual WWW sites should also provide virtual mail, or the ability to forward all mail to the virtual domain to another user or users. [Haskell Modules] .:: partners.skanska.com ::.
Virtual FTP or the ability to FTP using the standard host name "ftp.domain1.com" should also be configured by the WWW provider.