Server side programme has three functions:
I wrote the original controller in Perl, but as everyone complains that they only understand PHP, I have transcoded it so that people can see what it's doing. You may notice that I have provided a link to the PHP source on this slide.
The programme maintains state by writing the current slide number to a temporary file somewhere on the Web server - you get to choose. When a client polls the server, the current URI is returned.
The programme also provides the services of supplying the JavaSript included in the HTML files and, of course, the remote control page itself.
Next slide, please.