$5\mathrm{.}1.$ You are Network Security Analyst for ABC Holdings, discuss in detail the five fundamental characteristics of a secure network. $(10$ Marks$)\mathrm{.}5\mathrm{.}2$ When reading about network security, the Minister of Communication came upon the notion of screened subnets. Inform the minister of the purpose of the screened subnet and illustrate using a diagram.$(6$ Marks$)5\mathrm{.}3$ Discuss two different types of firewalls that can be deployed to secure a network in a screen host subnet. $(4$ Marks$)$