ISAPI Redirector filter
The purpose of that filter is redirecting requests sent to specific URLs to one or a
list of other URLs, shortly called 'mirrors'. Another advantage is that
you can give a ratio, called 'weight', that specifies how many requests
are redirected to each mirror URL. Application of the filter can be splitting the amount
of requests to an overloaded site between several mirrors. Also, by specifying different
weights, you can redirect more load to the mirrors with better bandwidth. Another possible
putting into pracice of this filter is accessing location with complicated URL by typing
something simplier, or even suppling several versions of a site, that are switched
The filter examines each incoming URL and processes it if present in the configuration.
For every URL that should be redirected there is a list of corresponding mirror
URLs, each with a weight. Redirector finds the mirror which is
now in turn and uses it. The process of redirection itself is realized by returning HTTP
error number 302 - Object Moved and sending the mirror URL in Location
header. When recieving that error the browser should automatically try the returned URL.