Web OS 10.0 Application Guide380 n Chapter 15: Content Intelligent Switching 212777-A, February 2002Virtual HostingWeb OS allows individuals and companies to have a presence on the Internet in the form of adedicated Web site address. For example, you can have a “www.site-a.com” and “www.site-b.com” instead of “www.hostsite.com/site-a” and “www.hostsite.com/site-b.”Service providers, on the other hand, do not want to deplete the pool of unique IP addresses bydedicating an individual IP address for each home page they host. By supporting an extension inHTTP 1.1 to include the host header, Web OS enables service providers to create a single virtualserver IP address to host multiple Web sites per customer, each with their own host name.N OTE – For SLB, one HTTP header is supported per virtual server.The following list provides more detail on virtual hosting with configuration information. An HTTP/1.0 request sent to an origin server (not a proxy server) is a partial URL insteadof a full URL.An example of the request that the origin server would see as follows:GET /products/180/ HTTP/1.0User-agent: Mozilla/3.0Accept: text/html, image/gif, image/jpegThe GET request does not include the host name. From the TCP/IP headers, the originserver knows the requests host name, port number, and protocol. With the extension to HTTP/1.1 to include the HTTP HOST: header, the above request toretrieve the URL “/www.nortelnetworks.com/ products/180” would look like this:GET /products/180/ HTTP/1.1Host: www.nortelnetworks.comUser-agent: Mozilla/3.0Accept: text/html, image/gif, image/jpegThe Host: header carries the hostname used to generate the IP address of the site. Based on the Host: header, the switch will forward the request to servers representing dif-ferent customers’ Web sites. The network administrator needs to define a domain name as part of the 128 supportedURL strings. The switch performs string matching; that is, the string “nortelnetworks.com” or“www.nortelnetworks.com” will match “www.nortelnetworks.com.”
