Zend Framework which is PHP based and Node.js which is JavaScript based don't have a common connection to pass data in a bi-directional nature. I was tasked with building a bridge of sorts that would utilize existing information from Zend Framework with the latest release of Socket.io's authorization mechanisms. (If you don't do this then arbitrary connections can happen and will be authorized.)

He starts with the code (on the Node.js side) to create a simple HTTP server to listen for the requests from the Zend Framework application. He gets into the details of how that all works before moving to the other side - a simple update to the authentication to store a session cookie with the information that is passed, via Socket.io to the waiting Node.js server for handling.