While trac is great, one thing I can't figure out is protect everything from anonymous to view. I can , however, remove all the permissions to the anonymous users in the admin, but that's troublesome, since you'll have to add them back to authenticated user.
So here's what I did to setup the basic authorization on Apache and Trac to protect everything.
Create the htpasswd file
htpasswd -c /home/projects/myproject/conf/htpasswd admin
Change the apache virtual host config file: