I have to implement a web app for a typical LAMP stack. One of the requirements is to publish "Facebook style" notifications on UI.
I'd prefer not to poll the web server to grab the data so I'm taking into consideration some push technologies (Atmosphere, Tornado...).
Since I have not found an out-of-the-box working solution in PHP, I wonder how to make the notification channel secure. I mean how to prevent User A read notifications of User B? Or even better, how to share session information between a LAMP stack and another Push server?