Question $4(20$ marks$)$

a$.$ Explain the concept of HMAC $($Hash$-$based Message Authentication Code$).(5$ marks$)$

b$.$ The primary purpose of a MAC is to provide message integrity and authenticity. How does it differ from a hash function, and what additional security property does a MAC provide? $(5$ marks$)$

c$.$ Explain the concept of digital signatures in public$-$key cryptography. How does it provide non$-$repudiation? $(5$ marks$)$

d$.$ How does steganography differ from cryptography? $(5$ marks$)$

Question $5(20$ marks$)$

a$.$ Explain the differences between digital signatures and electronic signatures. In what scenarios would you prefer one over the other? $(2$ marks$)$

$.$ Beyond email signing, what are some other common applications of digital signatures and digital certificates? $(2$ marks$)$

c$.$ In implementing best security practices, express four $(4)$ ways of securely storing data. $(8$ marks$)$

d$.$ Mention four $(4)$ proactive approaches to security that can help individuals and organizations to safeguard their information and build a more secure digital environment. $(8$ marks$)$