Your design does not meet any security standards, as one of the major factors is the single point of failure. There is no internal firewall to protect the internal/private network. The router in between will not be able to protect anything if the firewall gets compromised and it will open up the doors for attack. I would suggest you go through the above resources to get a good understanding of the design principles. Once you understand the principles you will be able to identify the problems and rectify them accordingly.
Dig Deeper on Network Infrastructure
Related Q&A from Puneet Mehta
Find out if there's a difference between a virtual private network (VPN) concentrator and a network access server (NAS) in this explanation from our ... Continue Reading
Our network security expert explains how to keep unauthorized users from accessing your router's IP address for Internet access in this advice ... Continue Reading
If you've used MAC address restriction to control your network access on your wireless router, can you extend this to your wired network? Our ... Continue Reading