Igital signed certificate to prevent security vulnerabilities

The final aim of this dissertation is to deploy digital signed certificate for an company, and define user policy for each staff/users (Identity, Authentication, Authorization).where we can control user access.

Logical Structure:

general introduction
description of the problem/field to investigate
main chapters(includes literature review , Methodology)
your solution/proposal

main text: Arial 11pt  1.5line space
references: Harvard

Please try to include the following as well,
What is digital signed certificate
How does digital signed certificate works
How to deploy user access policy
The future and present digital signed signature