Optimising Deployment

Eventually, Harry want to improve his web site performance, so he contracts a commercial HTTP service, which offers hardware based load balancing. Migration is simple, merely passing the DNS warrant and defining the URL's for the back ends. When the service is running, Harry cancels the URL's in the old HTTP service and closes it down. This migration is shown in figure .

**Figure:** Migration to a new HTTP service. The new service can run in parallel to the old during the migration process.
$\resizebox*{0.75\textwidth}{!}{\includegraphics{images/harrys_migration2.eps}}$

This deployment may optimise. The HTTP service is free to create new backends as required.

Jim Chapman 2001-08-16