Question $1($Marks: $25)$

Q$\mathrm{.}1\mathrm{.}1$ Using a suitable example, explain what is a cryptographic key, and what is it

used for?

$(3)$

Q$\mathrm{.}1\mathrm{.}2$ Describe three basic operations in cryptography. $(6)$

Q$\mathrm{.}1\mathrm{.}3$ Using examples, differentiate between symmetric and asymmetric encryption? $(8)$

Q$\mathrm{.}1\mathrm{.}4$ Using examples, differentiate between a digital signature and a digital

certificate?