Calling Controller with Cron Job

[eluser]bazianm[/eluser]
Hi,

I have to run a procedure once a day to send out emails to subscribed users. The application is written using CodeIgniter. Since this is a timed event, I was thinking I need to use a cron job to do it.

I have done some research and it seems like the general advice is to use wget in the cron job with a URL calling the job.

My questions: The application has security and I want to ensure that only the cron job can call the controller, not a user with a browser. Any ideas how I can accomplish this? Or, is there a better way to approach this in general?

Thanks in advance.