Nortel Networks WEB OS 212777 - Manual (Page 380)

Web OS 10.0 Application Guide
380 n Chapter 15: Content Intelligent Switching
212777-A, February 2002
Virtual Hosting
Web OS allows individuals and companies to have a presence on the Internet in the form of a
dedicated 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 by
dedicating an individual IP address for each home page they host. By supporting an extension in
HTTP 1.1 to include the host header, Web OS enables service providers to create a single virtual
server 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.
n
An HTTP/1.0 request sent to an origin server (not a proxy server) is a partial URL instead
of a full URL.
An example of the request that the origin server would see as follows:
GET /products/180/ HTTP/1.0
User-agent: Mozilla/3.0
Accept: text/html, image/gif, image/jpeg
The GET request does not include the host name. From the TCP/IP headers, the origin
server knows the requests host name, port number, and protocol.
n
With the extension to HTTP/1.1 to include the HTTP HOST: header, the above request to
retrieve the URL “/www.nortelnetworks.com/ products/180” would look like this:
GET /products/180/ HTTP/1.1
Host: www.nortelnetworks.com
User-agent: Mozilla/3.0
Accept: text/html, image/gif, image/jpeg
The Host: header carries the hostname used to generate the IP address of the site.
n
Based on the Host: header, the switch will forward the request to servers representing dif-
ferent customers’ Web sites.
n
The network administrator needs to define a domain name as part of the 128 supported
URL strings.
n
The switch performs string matching; that is, the string “nortelnetworks.com” or
“www.nortelnetworks.com” will match “www.nortelnetworks.com.”