a. What is blacklisting?
b. What is whitelisting?
c. We think that as a security principle which is preferable, whitelisting or blacklisting? Why?
d. Which one is better and more convenient for users, blacklisting or whitelisting? Why?
Please see necessary information chapter 13 : http://data.ceh.vn/Ebook/ebooks.shahed.biz/HACK/SECURITY/Information%20Security%20Principles%20and%20Practice%202nd%20Edition%20-%20Stamp.pdf