Security Project

HI,
i,m final year undergrad studying network engineering, and want to base my final year project around security issues. i know this is a mighty big area, so i am looking to narrow it down to areas such as "??????". This is where i thought some of you knowledegable people may be able to help. I aim to investigate issues such as Private wan's and tunneling protocols but dont know really where to start. Any help would be appreciated.
Thanks.