To start with,perimeter security is the using of firewalls which was used as first line of defense, ever since we felt the need of security system. Traditional methods have become obsolete and are not supported in Amazon Web services or Amzon EC2. Amazon prefers and supports security groups. A security group can be created for a jump box with ssh access. From that point a webserver and database group can be created. We can then add end number of machines to the webserver group and they all takes care of the data base. No one can directly ssh to any of the machines.