Best way to protect admin-directory

[eluser]Unknown[/eluser]
Hi,

I've been using codeigniter for some weeks now, and I must say it's a really neat framework. I developed the entire frontend of my website in just about a week of time, and now it's time to dive into the backend. Yay. Before, I've always used htaccess to protect a certain admin folder, but now I don't know how to accomplish that with CI.

I've placed an admin-folder inside the controllers directory, and can easily access its controllers and fucntions. But where do i put the htaccess/htpasswd file so it applies on the admin folder?

The thing is I want to be able to access all my previously written models and libraries which are to be shared by both the frontend and the backend. Perhaps it's easier to just use a session login? But I like htaccess protection, it's so convenient... Or are there any other solutions out there?

Thanks
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