How to install PSU-radius: 1. Download from http://ftp.psu.ac.th/pub/psu-radius/psu-radius.tgz to /tmp of local disk by: wget http://ftp.psu.ac.th/pub/psu-radius/psu-radius.tgz -P /tmp 2. Extract files by: tar -zxvpf /tmp/psu-radius.tgz -C /tmp 3. Get in the created directory by: cd /tmp/psu-radius 4. Install by: sudo sh install-psu-radius.sh 5. All done.